晶粒尺寸对气相沉积薄膜磁取向生长的影响研究  

Influence of grain size on the magnetic orientation growth of films prepared by vapor deposition in high magnetic field

作　　者：任树洋[1] 任忠鸣[1] 任维丽[1] 

机构地区：[1]上海大学材料科学与工程学院,上海200072

出　　处：《物理学报》2011年第1期449-453,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:50671060)资助的课题~~

摘　　要：为了研究强磁场下薄膜取向生长规律,采用真空蒸发气相沉积法分别制备了不同磁场方向生长的Zn和Bi薄膜.XRD结果发现磁化率差异较小的Zn薄膜在4T时产生了明显的取向生长,而磁化率差异较大的Bi薄膜在5T磁场强度还没有发生取向生长.SEM结果显示Zn薄膜和Bi薄膜晶粒尺寸上有明显的差别,利用Zn薄膜在4T磁场下的取向建立晶粒尺寸和取向生长的对应关系,提出薄膜发生取向时晶粒的磁化能须大于热能kT的420倍.薄膜是否发生取向生长取决于三个因素:薄膜单个晶粒的大小V,材料不同晶向的磁化率差异Δχ,施加磁场的大小B.The vacuum evaporation has been applied to prepare Zn and Bi films with different growth directions in order to investigate the orientation of films in magnetic fields. XRD results showed that magnetic orientation occurred in the Zn films with a smaller difference between magnetic susceptibilities of a-axis and c-axis compared with those of Bi in the magnetic field of 4T but the orientation did not take place in the Bi films prepared in a 5T magnetic field despite of a larger difference in magnetic susceptibilities. It was observed by SEM that the grain sizes in Zn and Bi films were markedly different. The relation between the grain size and the magnetic orientation was established in a magnetic field of 4T. The condition of orientation in films is that the magnetic energy should be 420 times larger than the thermal energy kT . The occurences of magnetic orientation growth in the films depends on the grain size of the film,the difference in magnetic susceptibility of the material and the intensity of the applied magnetic field,respectively.

关 键 词：强磁场 磁取向 薄膜生长 材料电磁加工 

分 类 号：O484.1[理学—固体物理]