FePtAg-C nanogranular film for ultrahigh density magnetic recording media

A FePtAg-C nanogranular film was studied for ultrahigh density perpendicular recording media with the density of 1 Tbits/in2 or even higher because of the strong anisotropy at FePt L10-phase. In experiments, a Fe47Pt42Ag11-C45% (6.6 nm) film was deposited on a silicon substrate with a MgO (12 nm) interlayer at 500 °C. The perpendicular coercivity of the film is 34 kOe, with a unit squareness. Bright-field TEM images show that the FePtAg-C nanogranular film has small and uniform grains of 6.8 ± 1.6 nm. More work of high-resolution TEM imaging shows excellent L10-ordering for this film, consistent with the texture measurement by XRD. The measurement of remnant coercivity proves that it has an energy barrier of 310 kBT at room temperature, meaning excellent thermal stability. As a result, FePtAg-C nanogranular film is a qualified candidate for high-density magnetic recording media.