Investigation of Fe-Si-N films as magnetic overcoat for high density recording disk drives

A 50-nm-thick Fe-Si-N films were deposited via reactive magnetron cosputtering of independent Fe and Si targets, in Ar/N(2) gas mixture, under different dc Fe target power conditions. Magnetic properties, mechanical hardness and tribological properties were characterized as a function of the Fe target power by magnetometry, nanoindentation, and nanoscratch testing, respectively. Deposited samples were found to be ferromagnetic with a coercivity of approximately 20 Oe and a saturation magnetization increasing from 200 to 1100 emu/cm(3) as a function of Fe sputter power, i.e., values typical of soft magnetic materials. The mechanical hardness was found to be between 50% and 70% of the hardness of a pure SiN(x) film. Nanotribological properties of films deposited with a Fe target power >= 80 W degraded rapidly. (C) 2010 American Institute of Physics. [doi:10.1063/1.3484035]