Thermal stability of narrow track bits in a 5 Gbit/in(2) medium

The thermal stability of high density written bits in a 5 Gbit/in(2) CoCrPtTa/CrMo medium is examined using a magnetic force microscope. Images of the same 0.8 mu m-track all-ones pattern were taken before and after various anneal schedules. Written bits, which for the measured magnetocrystalline anisotropy and switching volume, are predicted by simulation studies to be thermally unstable reveal no significant degradation with annealing up to 490 K for 2 hours, This discrepancy emphasizes the need for more realistic theoretical models.