HIGH-DENSITY RECORDING CAPABILITY OF GRANULAR MEDIA COMPOSED OF CO-PTGRAINS AND SIO2 MATRIX

Co-Pt and SiO2 granular films were prepared on a Cr seed layer. Co-Pt grains dispersed in the SiO2 matrix discretely. Conical grains grew in contact with the Cr layer and spherical grains grew between the conic al ones. Coercivity exceeded 2 kOe and coercive squareness reached abo ut 0.7 at a remanent magnetic moment of 0.4 memu/cm(2). Activating mag netic moment was 10(-15) emu and the index of the thermal stability wa s about 100. Bit error rate was held below 10(-5) up to a Linear densi ty of 280 kfci. The recording pattern at the track width of 1 mu m was clearly visible. The Co-Pt and SiO2 granular media have potential for 5 Gb/in(2) recording.