利用磁控溅射方法,在加热的单晶MgO(100)基片上制备了以AlN为母体的FePt薄膜,再经过真空热处理后,得到了具有垂直磁各向异性且无磁交换耦合作用的FePt薄膜;同时,研究了掺杂AlN含量、薄膜的厚度及退火温度对薄膜的磁性能的影响。结果表明,非磁性相AlN的添加能够降低磁交换耦合作用,但同时也会破坏薄膜的垂直磁各向异性。降低薄膜厚度,有利于改善薄膜的垂直磁各向异性,FePt-AlN薄膜的厚度为6nm且掺杂AIN含量达到40%时,经650℃热处理1h后薄膜具有良好垂直磁各向异性、适中矫顽力且无磁交换耦合作用。
FePt-AlN nano-films were prepared on single crystal MgO (100) substrates preheated at 200℃ with magnetron sputtering. L10-FePt-AIN films with perpendicular magnetic anisotropy and no interparticle exchange coupling were obtained after vacuum annealing. The influence of AlN content,thickness of FePt-AlN films and annealing temperature on magnetic properties of films were also studied. Results show that the interparticle exchange coupling was decreased with increasing the content of AlN. However, doping excessive AlN can destroy the perpendicular magnetic anisotropy of films. To further improve perpendicular magnetic anisotropy of films, reducing the thickness of FePt-AlN films has been adopted. When the thickness of FePt-AlN films is 6 nm and AlN content is 40%,the film possesses excellent perpendicular magnetic anisotropy,moderate coereivity and no interparticle exchange coupling after annealing at 650℃ for 1h.