不同生长条件下合成的金刚石晶体缺陷的特征研究

Studies of characteristics of crystal defects in diamond synthesized under different conditions

采用同步辐射白光貌相术对四组采用不同生长条件合成的金刚石晶体进行了研究,分析了四组金刚石晶体内部缺陷的形貌特征,并对部分缺陷的特征量进行了计算。不同生长条件下合成的金刚石样品不仅颜色、晶形不同,晶体内部的缺陷类型和分布特征也明显不同。A组样品中的晶体缺陷以起源于籽晶表面的位错为主,少量位错起源于晶体的内部。局部存在层错,个别晶体具有孪晶界、片状应力区和生长带。在B组和C组样品中存在的主要缺陷为生长带。D组样品中的晶体缺陷主要为生长带和位错束。研究结果表明,同种生长条件合成的金刚石晶体缺陷特征具有相似性,而不同生长条件合成的金刚石晶体缺陷则具有较大的差异。

Four groups of diamonds synthesized under different conditions were studied using continuous spectra synchrotron radiation and the characters of internal defects of the diamonds were analyzed, and the directions of some defects were calculated. Not only the color and crystal form were different, but also the type and the distribution of internal defects of the diamond synthesized under different conditions were different. The main crystal defects in samples of Group A were the dislocations originated from the seed crystal and a few dislocations originated from the inner of crystals could also be found. Stacking faults exited in part, the boundary of twin crystals, sheet stress sections and growth bands existed in specific crystals. Growth bands were the main defects existed in sample of Group B and C. Growth bands and dislocations were the main defects existed in Group D. The research result indicated that the characters of crystal defects of diamond synthesized under same condition were similar and the characters of crystal defects of diamond synthesized under different conditions were different.