Controlling the crystallographic orientation in ultrathin L1/sub 0/ FePt[111] films on MgO[111] underlayer

Controlling the crystallographic orientation in ultrathin FePt longitudinal media for ultrahigh recording density is discussed with introducing sputtered MgO[111] underlayers selected as a template for inducing [111] texture in the FePt films. The MgO[111] underlayers significantly enhanced the crystallographic texture of FePt[111] for films as thin as 10 nm or less. Full width at half maximum (FWHM) of FePt[111] reflection measured from XRD rocking curves and coercivity squareness (S*) confirmed the strong in-plane texture of the FePt films deposited on MgO(111) underlayers. FWHM and S* were 8/spl deg/ and 0.8, respectively. High coercivity of 3200 Oe could be achieved in films with very low M/sub r/t of 0.3 memu/cm/sup 2/ at moderate annealing temperature (/spl les/500/spl deg/C) which retained small grains.