3 T强磁场对真空蒸发Zn薄膜晶体结构的影响

在3 T强磁场下采用真空蒸发沉积在玻璃基片上制备了三种厚度分别为1,2，3 μm的Zn薄膜，并和无磁场下制备的薄膜进行了对比研究.对施加磁场和无磁场环境下制备的试样分别进行了X射线衍射研究.研究表明，3 T磁场下制备的Zn薄膜都是沿（002）面取向，而0 T磁场下制备的薄膜随着厚度的增加c轴取向逐渐减弱. 3 T磁场的取向作用可以维持Zn晶粒沿着c轴取向.利用扫描电子显微镜对薄膜表面形貌的研究发现，施加磁场制备的Zn薄膜表面晶粒要比无磁场条件下制备的薄膜有明显的细化.对磁场下Zn原子团形成进行了热力学分析，推导了磁场作用下的临界形核半径r^*_M和临界形核自由能ΔG^*_M.初步分析表明，r^*_M和ΔG^*_M减小从而增加临界形核浓度是Zn晶粒细化的原因. 关键词： 强磁场 晶体结构 真空蒸发沉积 薄膜

Influence of 3 T magnetic field on the crystal structure of Zn films prepared by vapor deposition

Zinc films with three different thicknesses in the range of 1—3 μm were deposited on a glass substrate under a high magnetic field of 3 T, and compared with the samples prepared without magnetic field. It’s indicated that the all samples in 3 T magnetic field tend to align in the c-axis direction of zinc crystal and those prepared under in 0 T have lower intensity in c-axis with the thickness increasing, as shown by the X-ray diffraction results. From the scanning electron microscope photographs we found that crystals of zinc films prepared in 3 T magnetic field have refined appearance compared to the ones without magnetic field. Thermodynamic theory was used to analyze the coacervation of zinc aggregates. Preliminary analysis shows that the critical nucleation radius r^*_M and critical nucleation Gibbs free energy ΔG^*_M in the magnetic field is less than r^* and ΔG^* in normal state. Thereby, the nucleation intensity of zinc crystals in 3 T magnetic field is larger than that in 0 T and accordingly the refine ment phenomenon ensues.