直拉法YAG的小面生长和邻位面生长

对于在YAG晶体生长过程中用“倾倒法”获得的固液界面进行了宏观观测和显微研究。确定了沿不同取向生长的固液界面上出现的小面的面指数。在〈001〉生长的凹形固液界面上观测到{112}小面;并对其邻位面进行了显微观测,发现邻位面是由奇异面上一定组态的台阶构成的,并且观测到台阶运动以及台阶和包裹物交互作用的迹象。进一步对比了凹形界面和凸形界面的生长,发现在界面的显微结构以及小面和内核的对应关系上存有差异,认为这差异是来源于不同宏观形状的界面对奇异面生长机制的影响,据此分析了凸形界面和凹形界面上奇异面生长的微观机制。关键词：

THE GROWTH OF FACETS AND VICINAL INTERFACES ON CZOCHRALSKI-GROWN YAG SINGLE CRYSTALS

In this paper, we studied the macro-morphology and micro-structure of crystal-molt interfaces, which was exposed by rapid separating the growing crystal from the melt. We have determined the indices of the facets revealed on the interface of Czochralski-pulled YAG single crystals with various orientations. The facets have been discovered on the concave interface as well as on convex interface of <100>-oriented grown YAG single crystals. We have observed the micro-structure of vicinal interface, which is composed of sections of singular surface dispersed with steps. The experimental evidence for the step movement as well as the interaction of steps with inclusions on these interfaces is presented.The micro-structure of the interfaces and the correspondence between the facets and the core for concave interface growth are discussed, and it is implied that the macro-shapes of interface influence the micro-mechanism of growth. The growth mechanism for concave and convex interfaces based on these considerations is then developed.