Nanocomposite CoPt:C films for extremely high-density recording

Nanocomposite CoPt films were investigated as potential media for extremely high-density recording. An annealing temperature of over 600°C is necessary to form nanocomposite CoPt films consisting of C matrix and fct CoPt nanocrystallites with grain sizes of 8-20 nm and coercivities of 3-12 kOe. Coercivity and grain size increase with increasing annealing temperature and decreasing C concentration and they are insensitive to film thickness. The average activation volumes are about 0.9×10-18cm3. The properties of these nanocomposite CoPt films can be tailored to satisfy the thermal stability, coercivity, and media noise requirements for extremely high-density recording. © 1999 American Institute of Physics.