脉冲电子辐照下P型硅材料短期退火的数值模拟  

Numeircal Simulation on the Short-Term Annealing in P-Type Silicon Materials Irradiated by Pulsed Electrons

作　　者：白小燕 刘岩 王桂珍 齐超 金晓明 李瑞宾 王晨辉 李俊霖 BAI Xiaoyan;LIU Yan;WANG Guizhen;QI Chao;JIN Xiaoming;LI Ruibin;WANG Chenhui;LI Junlin(National Key Laboratory of Intense Pulsed Radiation Simulation and Effect,Xi’an 710024,China)

机构地区：[1]强脉冲辐射环境模拟与效应全国重点实验室,西安710024

出　　处：《现代应用物理》2024年第2期132-138,共7页Modern Applied Physics

基　　金：强脉冲辐射环境模拟与效应全国重点实验室基金资助项目(SKLIPR1804)。

摘　　要：建立了脉冲电子辐照下硅材料短期退火的数值模拟方法,主要分为两步:一是基于连续性方程得到缺陷和载流子密度的时间演化;二是基于SRH复合理论计算空穴寿命,然后根据空穴寿命计算短期退火因子。数值模拟结果表明,40 ns脉冲电子辐照下P型硅材料的短期退火可以分为两个阶段:第一个阶段发生在10^(-5)~10^(-3)s,主要是硅间隙原子被硼替位原子捕获形成硼间隙原子的过程,短期退火因子从10下降到3;第二个阶段发生在0.1~1 s,主要是空穴被氧原子捕获形成VO的过程,短期退火因子从3下降到1。脉冲电子在材料中沉积的电离能导致大量电子空穴对产生,对位移损伤短期退火主要产生两方面的影响:一方面增强了硅间隙原子的扩散能力,加速了硼间隙原子的形成;另一方面对空穴寿命产生影响。与早期文献中相同条件下的实验结果对比可发现,本文模拟结果与实验结果符合得较好。In this paper,a numerical simulation method of the short-term annealing in silicon materials irradiated by pulsed electrons is developed.The method is mainly divided into two steps.Firstly,the time evolutions of defect and carrier densities are obtained based on the continuity equations.Secondly,the minority carrier lifetime is calculated based on the SRH recombination mechanisms.The simulation results show that the short-term annealing process can be divided into two stages.The first stage occurs from 10-5 to 10-3 s,during which the silicon interstitials react with substitutional boron atoms to create boron interstitials and the short-term annealing factor decreases from 10 to 3.The second stage occurs from 0.1 to 1 s,during which the vacancies react with interstitial oxygen atoms to create vacancy-oxygen pairs VO and the annealing factor decreases from 3 to 1.The great quantity of electron-hole pairs generated during the pulse have two effects on the short-term annealing process of displacement damage.On the one hand,the diffusivity of silicon interstitials is enhanced and then the formation of boron interstitials is accelerated,and on the other hand,the minority carrier lifetime is affected.Compared with the experimental result under the same condition in the early literature,it is indicated that only the second stage is observed in the experiment,and the simulation result is in good agreement with the experimental result.Compared with the simulation results by other researchers,the result in this paper is more closer to the experimental result,attributed to the calculation of the minority carrier lifetime from the defect densities.

关 键 词：脉冲电子 短期退火 空穴寿命 连续性方程 SRH复合 

分 类 号：TL92[核科学技术—核燃料循环与材料] O474[理学—半导体物理]