温梯法生长CaF_2晶体中包裹物的研究

Study of the Inclusion of Calcium Fluoride Crystals Grown by TGT

本文对温度梯度法生长的氟化钙(CaF2)晶体中的包裹物进行了研究,用光学显微镜和SEM观察了包裹物的形貌,对晶体中的包裹物和透明部分作了微区EDX成分分析,对包裹物所含的杂质进行了解释,提出了减小或消除包裹物的措施。分析结果表明:包裹物的主要成分是碳和氧,碳来源于石墨坩埚和石墨发热体,而杂质氧则来源于原料中的含氧化合物和生长过程气氛中氧的进入。

This paper studied the inclusion in the calcium fluoride crystals grown by temperature gradient technique (TGT).The inclusion was observed by means of optical microscope and SEM. The components of the inclusion and the transparent crystals were analyzed by EDX.The reason why the impurities exist in the crystal was given.The results show that the main components of inclusion are carbon and oxygen.Carbon impurity comes from graphite crucible and heater,while oxygen impurity from the oxides in the raw material and the oxygen in the growth atmosphere.At last,the paper put forward the measures to resolve this problem.