copt垂直磁各向异性薄膜制备及性能分析word格式论文.docxVIP

AbstractWith the increasing demand for greater capacity and higher density of the recording media, the traditional longitudinal magnetic recording technology has met its physical limit. The perpendicular magnetic recording media has been proposed in magnetic recording technology to overcome the problem of superparamagnetic limits. L10-CoPt thin film media with high magnetocrystalline anisotropy energy has attracted considerable interests in the near future. The face cubic tetragonal (fct) ordered alloys exhibit great potential for high-density magnetic media because of their capability to achieve extremely small grain sizes to keep thermal stability, high coercivity and magnetocrystalline anisotropy energy(4.9×107erg/cm3for CoPt).In this thesis, CoPt films were fabricated by DC magnetron sputtering system on a P-type thermally oxidized substrate of Si/SiO2. First of all, we studied the effect of heatingof the substrate and different thicknesses on the magnetic properties of Co78Pt22 film，magnetic properties of Co-Pt alloy films with different atomic ratios and Ta seedlayer .Moreover, the effects of sputtering parameters （such as sputtering power、the pressure of Ar ）on CoPt film magnetic properties were investigated. The fabricationparameters have been optimized to improve the magnetic properties of CoPt/Ta.Last but not least, some modern analytical test methods of XRD, VSM, XPS were applied to research the microstructures and magnetic properties of CoPt / Ta film and CoPt film. In this study, we reported that the magnetic properties of CoPt thin films capped with Ta layer were better than those of CoPt single-layer. In the annealing process,Ta prevented CoPt films from corrosion and oxidation because Ta can react with oxygen to form protective coating layer. The perpendicular magnetic properties were improved greatly. Besides, thermal diffusion of Ta atoms into the CoPt layer signi?cantly decreased theexchange interaction among the magnetic