FePtAg-C nanogranular film for ultrahigh density magnetic recording media

摘要

A FePtAg-C nanogranular film was studied for ultrahigh density perpendicular recording media with the density of 1 Tbits/in~2 or even higher because of the strong anisotropy at FePt L1_0-phase. In experiments, a Fe_(47)Pt_(42)Ag_(11)-C45% (6.6 nm) film was deposited on a silicon substrate with a MgO (12 nm) interlayer at 500 ℃. 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 L1_0-ordering for this film, consistent with the texture measurement by XRD. The measurement of remnant coercivity proves that it has an energy barrier of 310k_BT at room temperature, meaning excellent thermal stability. As a result, FePtAg-C nanogranular film is a qualified candidate for high-density magnetic recording media.