Textured growth of highly coercive L10 ordered FePt thin films on single crystalline and amorphous substrates

FePt films have been prepared by pulsed laser deposition at a temperature of 800 °C onto (001) oriented single crystalline (MgO, SrTiO3) as well as amorphous substrates (Si3N4, glass) with and without a (001) textured MgO buffer layer. Although all films have been prepared under identical conditions, significant differences in coercivity are observed. Very high values of up to 5.6 T have been measured for the epitaxial films, while on the amorphous substrates the coercivities range between 0.8 and 2.0 T. We analyze whether changes in intrinsic or extrinsic properties due to a modified microstructure are responsible for these differences.