CVD-ZnS胞状生长现象对材料结构与性能的影响

采用化学气相沉积法(CVD)制备大尺寸ZnS晶体(CVD-ZnS),利用扫描电子显微镜、透射电子显微镜、X射线衍射分析对CVD-ZnS内部的胞状结构进行表征,表明胞状生长现象能改变CVD-ZnS材料内部的晶粒生长方向、分布方式,但对材料内部的物相、元素分布并未造成显著影响;通过对胞状物密集区的光学均匀性检测,分别为2.71×10^-5和2.85×10^-5,均方根值分别为6.46×10^-6和4.98×10^-6,正常区域的样品光学均匀性为9.53×10^-6,均方根值为1.51×10^-6,表明胞状物的存在会降低CVD-ZnS材料的光学均匀性;采用三点弯曲法测试材料弯曲强度,四组弯曲强度数据表明CVD-ZnS正常区的弯曲强度明显高于CVD-ZnS胞状物密集区。

Effect of Cellular Growth on Structure and Performance of CVD-ZnS

Large-size ZnS crystals(CVD-ZnS)were prepared by chemical vapor deposition(CVD).The cellular structure in CVD-ZnS was characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray diffraction analysis(XRD),showing that growth direction and distribution mode of grains were changed by cellular structure.However,it has no significant effect on the phase,element distribution.Detection of optical homogeneity was implemented in dense areas of cellular matter and normal areas,optical homogeneity is respectively 2.71×10^-5,2.85×10^-5 and 9.53×10^-6,root mean square value is respectively 6.46×10^-6,4.98×10^-6 and 1.51×10^-6,indicating the existence of cytoplasm can reduce the optical uniformity of CVD-ZnS materials.The bending strength of materials was measured by three-point bending method,four groups of bending strength data shows that the bending strength of CVD-ZnS normal zone was significantly higher than that of CVD-ZnS cell-dense zone.