Interlayer Thickness, Transition Parameter, and Intergranular Exchange in Perpendicular Oxide Media

The effect of intergranular exchange on the transition parameter (a) in perpendicular oxide composite media was investigated. Two different methods were used to vary the amount of intergranular exchange present in the films. The inter layer (IL) thickness was varied for one series of sample, while for the other, the oxygen (O₂) flow was changed during deposition. The transition parameter was extracted using a read-back model to fit experimental rolloff curves for both series. The exchange was quantified by calculating alpha values from the experimental (M-H) loops. It was found that increasing the intergranular exchange in the recording layer lead to a reduction of the transition parameter by up to 12% for alpha values in the range of 2.2. These results were achieved for both methods of varying exchange and lead to very similar range of alpha values