高纯硅辐射损伤的正电子湮没和扰动角关联研究

A study of radation damage in high purity Si by positron annihilation and perturbed angular correlation methods

采用正电子湮没和扰动角关联方法研究了１．４５×１０２０、３．１０×１０１７ｎ／ｃｍ２中子辐照和５×１０１１／ｃｍ２１７８Ｗ重离子辐照单晶硅引起的辐射损伤及其退火效应。实验测量的正电子湮没寿命和四极相互作用频率表明在Ｓｉ中存在氧一单空位对．高中子剂量和重离子辐照Ｓｉ后，用两种方法都观察到了双空位复合成四空位。

The positron annihilation and perturbed angular correlation methods have been used to study the radiation damage and its thermal annealing behavior in the single crystal Si irradiated with fast neutrons of 1.45 ×1020/cm2 and 3.10×1017/cm2 and with 178W heavy ions of 5×1011/cm2,respectively.The measured positron lifetimes and quadrupole interaction frequencies show the existence of the monovacancysubstitutional oxygen complexes in the irradiated single crystal silicon.In silicon samples irradiated with 1.45×1020/cm2 neutron and heavy ions the combination of di-vacancies into quadri-vacancies has been observed by both methods.