硅单粒子位移损伤多尺度模拟研究  

Multi-scale simulations of single particle displacement damage in silicon

作　　者：唐杜[1] 贺朝会[1] 臧航[1] 李永宏[1] 熊涔 张晋新[1] 张鹏[1] 谭鹏康 

机构地区：[1]西安交通大学核科学与技术学院,西安710049

出　　处：《物理学报》2016年第8期193-200,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11175138);国家自然科学基金重点项目(批准号:11235008);国家重点实验室项目(批准号:20140134);高等学校博士学科点专项科研基金(批准号:20130201120090)资助的课题~~

摘　　要：本文结合分子动力学方法和动力学蒙特卡罗方法,研究了单个粒子入射硅引起的位移损伤缺陷的产生和演化过程;基于Shockley-Read-Hall理论计算了单个粒子入射引起的位移损伤缺陷导致的泄漏电流增加及其演化过程,比较了缺陷退火因子与泄漏电流退火因子之间的差异,并将计算结果与实验值进行了对比.结果表明,计算泄漏电流时,仅考虑一种缺陷的情况下缺陷退火因子与泄漏电流退火因子相同,考虑两种缺陷类型情况下二者在数值上有所区别,但缺陷退火因子仍能在一定程度上反映泄漏电流的退火行为.分子动力学模拟中采用Stillinger-Weber势函数和Tersoff势函数时缺陷退火因子和泄漏电流退火因子与实验结果一致,基于Stillinger-Weber势函数的计算结果与实验值更为接近.Silicon devices are extensively used in space and other radiation-rich environments. They must withstand radiation damage processes that occur over wide range of time and length. Ion implantation technique, one of the most important process in the fabrication of integrated circuits, can also create the displacement damage in silicon lattice. Exposure of silicon wafer or silicon device to radiation causes the creations of variety of defects and has adverse effects on the electrical properties of devices. Although phenomenological studies on the radiation effects in silicon have been carried out in the past decades, the features of multi-scale of displacement damage make it difficult to characterize the defect production and evolution experimentally or theoretically. Recently, the silicon device with ultra-low leakage current was shown to be very sensitive to the permanent displacement damage induced by single particles, called single particle displacement damage（SPDD） event. To the best of our knowledge, the investigation of single particle displacement damage（SPDD）event in silicon device by the coupling molecular dynamics（MD） and kinetic Monte Carlo（KMC） techniques has not yet been reported so far. In this paper, MD simulations are combined with KMC simulations to investigate the formation and evolution of SPDD event in silicon. In MD simulations, Tersoff potential is used to describe the Si-Si atomic interactions.The potential smoothly joins to Ziegler-Biersack-Littmark potential that describes the energetic short range interactions well. All atoms in the MD cell are allowed to evolve 0.205 ns to track the damage production and short-term evolution.A multi-phase simulations are performed to improve the simulation efficiency. Then the nearest neighbor criterion is employed to identify the configurations and spatial distributions of interstitials and vacancies, which are used as input in KMC simulations to study the thermal diffusion and interactions of those defects in the time interval from 0.205

关 键 词：位移损伤 缺陷 退火因子 泄漏电流 

分 类 号：O561[理学—原子与分子物理]