辐照与退火对金刚石氮空位色心产率的影响

Effects of Irradiation and Annealing on Nitrogen-Vacancy Center Yield in Diamond

采用高能电子辐照结合真空退火,在金刚石内部形成氮空位色心。对比研究了辐照与退火前后金刚石宏观颜色变化及内部缺陷转变,讨论了不同辐照剂量和真空退火温度对氮空位产率的影响规律。结果显示,氮空位色心浓度随着辐照剂量的增加呈现先升高后降低的趋势,这是由于辐照剂量越高则空位更容易形成空位簇,空位簇在退火过程中不能形成氮空位色心。氮空位色心浓度随退火温度的升高逐渐增加,在800~900℃区间达到饱和,当温度继续升高时,氮空位色心浓度反而下降,这源于辐照过程产生的间隙原子在高温下与氮空位的相互作用。

In this paper,nitrogen-vacancy centers in diamonds are created by high-energy electron irradiation and vacuum annealing.The macroscopic color changes and internal defect transformations in those diamonds before and after irradiation and annealing are investigated.The effects of irradiation dose and vacuum annealing temperature on the yield of nitrogen vacancies are discussed.The results show that the concentration of nitrogen-vacancy centers rises and then drops as irradiation dose increases.This is because under a higher irradiation dose,vacancies are more likely to form vacancy clusters,which do not constitute nitrogen-vacancy centers during the annealing process.The concentration of nitrogenvacancy centers increases with the increasing annealing temperature and then saturates in the temperature range of 800-900℃.As the temperature further increases,the concentration declines due to the interaction of nitrogen vacancies with interstitial atoms generated during the irradiation process under a high temperature.