【作者】 张峰；

【导师】 黄致新；

【作者基本信息】 华中师范大学 ， 材料物理与化学， 2008， 硕士

【摘要】 本文采用磁控溅射方法制备了SmCo系列单层和多层磁性薄膜,并采用X射线能量色散谱仪(EDS)、X射线衍射分析仪(XRD)、振动样品磁强计(VSM)和扫描隧道显微镜(STM)等对薄膜的成分、结构、磁学性能和表面形貌进行了研究,研究发现:(1)溅射工艺参数对SmCo薄膜磁性能的影响明显。通过优化溅射工艺参数,得出了最佳溅射工艺条件:磁性层溅射功率为60W,溅射气压为0.5Pa,溅射时间为8min;底层溅射功率为125W,溅射气压为0.5Pa,溅射时间为4min。此时,SmCo磁性薄膜的面内矫顽力高达2.79×10~5A/m,所制备的SmCo薄膜为面内磁化膜。(2)底层对SmCo薄膜磁性能也有影响。通过制备不同底层的SmCo薄膜,我们发现以Cu作为底层制备的SmCo薄膜磁性能更好,薄膜矫顽力分别比用Cr、Ti作底层时高出56%,40%。同时发现,溅射Cu底层时基片加温至150℃的时候,SmCo薄膜磁化方向有从面内向垂直方向转变的趋势。所制备出SmCo/Cu垂直磁化薄膜的矫顽力高达4.86×10~5A/m;通过分析SmCo薄膜在不同温度下的表面形貌,发现150℃时薄膜的晶粒尺寸较小,薄膜的矫顽力有大幅度的提高。(3)Cr中间层对SmCo/TbFeCo多层膜磁交换耦合性能具有影响。研究发现,多层膜系统的磁性能随着Cr中间层厚度的变化而发生改变,尤其是薄膜的饱和磁化强度和矫顽力,显示出周期性振荡的特性。通过扫描隧道显微镜观察发现,有Cr中间层时SmCo薄膜的晶粒尺寸要比无Cr中间层时的SmCo薄膜要小得多。而且,我们还发现SmCo薄膜的平均晶粒尺寸随着Cr中间层厚度的增加而显示出减小的趋势。通过研究我们可以看出,薄膜矫顽力的变化主要是由于Cr中间层的加入改变了SmCo薄膜的微观结构,而饱和磁化强度的变化则是与薄膜的磁交换耦合作用有关。更多还原

【Abstract】 In this thesis,SmCo series single and multilayer magnetic thin films are fabricated by using RF-magnetron sputtering system.With the results of EDS、XRD、VSM and STM, we can get the following conclusions:(1)The effect of sputtering parameters on magnetic properties of SmCo thin films is obvious.Through optimizing the sputtering parameters,the optimal sputtering parameters are obtained.It is found that when the sputtering power,sputtering pressure and sputtering time of the SmCo thin films and the underlayer are 60W,0.5Pa and 8min, 125W,0.5Pa and 4min,respectively,the in plane coercivity is as high as 2.79×10~5A/m.(2)The underlayer can effect the magnetic properties of SmCo thin films.The VSM measurements reveales that SmCo thin films will possess better magnetic properties with Cu as underlayer than Ti and Cr.Compared with Cr and Ti as underlayer,the coercivity of SmCo thin films with Cu underlayer is higher 56%and 40%,respectively.The magnetization orientation of the films changes from in-plane to perpendicular when the temperature of Cu underlayer is 150℃.The SmCo/Cu thin films with the coercivity up to 4.86×10~5A/m are prepared.The STM images reveales that SmCo/Cu thin films will possess better magnetic properties with Cu underlayer at 150℃.(3)Cr interlayer affects the magnetic exchange coupling of SmCo/Cr/TbFeCo multilayer thin films.It is found that the magnetic properties of multilayers vary with the thickness of Cr interlayer,especially the values of saturation magnetization Ms and the coercivity Hc fluctuate periodically with the thickness of Cr interlayer.The STM images reveales that grain size of SmCo thin film with inserting Cr interlayer is much smaller than pure SmCo thin film.And the variation of coercivity Hc is attributed to the microstructure change of SmCo layer influenced by Cr interlayer,the variation of Ms is related to interlayer exchange coupling.更多还原