本征点缺陷对硅材料响应特性的影响分析  

Effects of Intrinsic Point Defects on Response Characteristics of Silicon

作　　者：吕彤 张蓉竹[1] LüTong;Zhang Rongzhu(College of Electronics and Information Engineering,Sichuan University,Chengdu 610065,Sichuan,China)

机构地区：[1]四川大学电子信息学院,四川成都610065

出　　处：《光学学报》2023年第21期229-236,共8页Acta Optica Sinica

摘　　要：针对硅基材料在1319 nm激光辐照下产生带外响应的问题,研究了硅材料中的本征点缺陷对响应特性的影响。根据第一性原理建立了晶胞模型,比较了几种典型点缺陷状态下硅材料的能级分布特性,在此基础上分析了本征点缺陷对硅材料光电响应特性的影响。结果表明:空位和自间隙原子两类缺陷都能够改变硅材料的能带结构和响应特性。532 nm激光辐照时,硅基光敏单元的输出饱和阈值明显降低。当辐照波长为1319 nm时,硅材料产生明显的带外响应,其中贡献最大的是四面体间隙缺陷。此时材料带隙消失,吸收系数高达50391 cm^(-1),折射率减小约25.99%,因此硅材料在1319 nm处的量子效率值最大,导致光电响应最为强烈,输出饱和阈值最小,为0.0015 W·cm^(-2)。Objective Silicon materials are widely used in the field of photoelectric detection because of their excellent optoelectronic properties.Theoretically,the long wave response limit of intrinsic silicon is about 1100 nm.However,it is found in experiments that silicon-based devices will also produce out-of-band response output under the irradiation of 1319 nm laser,which indicates that the photoelectric response characteristics of silicon materials deviate from the theoretical situation,which will cause significant interference to high-precision detection.The out-of-band responses of silicon-based devices indicate that the energy band structure of silicon materials has changed.Since intrinsic point defects can change the energy levels of silicon materials,it is necessary to study the effects of intrinsic point defects in different states on the photoelectric response characteristics of silicon materials.The theoretical analysis results can provide a reference for the subsequent application and development of silicon-based optoelectronic devices in the field of high-precision detection.Methods The intrinsic point defects in single crystal silicon can change the band structures of silicon materials,thereby affecting the quality of materials and the performance of devices.Therefore,according to the intrinsic point defects of vacancies and self-interstitial atoms in single crystal silicon,cell models with defects in different states are established based on the first principles.The influence of intrinsic point defects on the band structure of silicon materials and the change in the optical properties of silicon materials under the influence of defects are analyzed.On this basis,the response output characteristics of silicon materials with intrinsic point defects under the irradiation of 532 nm and 1319 nm are calculated.Results and Discussions The vacancy defects and self-interstitial atomic defects in different states will introduce defect energy levels into the energy level distribution of silicon,leading to the decre

关 键 词：材料 单晶硅 光电响应 本征点缺陷 第一性原理 

分 类 号：O436[机械工程—光学工程]