低过偏压下高增益单光子雪崩二极管的设计与验证  

Design and Verification of Single-Photon Avalanche Diode with High Gain at Low Overbias Voltage

作　　者：易荣清 汪洋 曹智祥 金湘亮 Yi Rongqing;Wang Yang;Cao Zhixiang;Jin Xiangliang(School of Physics and Electronics,Hunan Normal University,Changsha 410081,Hunan,China)

机构地区：[1]湖南师范大学物理与电子科学学院,湖南长沙410081

出　　处：《光学学报》2023年第23期147-154,共8页Acta Optica Sinica

基　　金：国家自然科学基金(62174052,61827812);湖南省科技部湖湘高水平人才聚集项目(2019RS1037);湖南省科技厅创新项目(2020GK2018)。

摘　　要：单光子雪崩二极管(SPAD)可以检测到异常微弱的光信号,可广泛应用于目标跟踪、自动驾驶、荧光检测等领域。本文基于180 nm标准双极-互补金属氧化物半导体-双扩散金属氧化物半导体(BCD)工艺,设计了一种低过偏压下具有高光子检测概率(PDP)的SPAD器件。该器件在440~740 nm范围内具有良好的光谱响应。采用半径为10μm的N+/P阱形成PN结作为感光区域,由N阱形成一个能有效防止边缘击穿的保护环。应用计算机技术辅助设计(TCAD)软件对SPAD的基本工作原理进行了定性分析,并通过建立的测试平台获得了设备的实际电气参数。测试结果表明,在1 V的过量偏置电压下,在480~660 nm的波长范围内,该器件可达到30%以上的PDP。在560 nm时,PDP峰值为42.7%,暗计数率为11.5 Hz/μm^(2)。最后通过设计VerilogA混合模型验证了器件的模拟结果和实测结果之间具有良好一致性。Objective Photoelectric detection plays an important role in various fields such as fluorescence microscopes,photodetectors,and medical three-dimensional imaging.With the emergence of photomultiplier tubes(PMTs),avalanche photodiodes(APDs),and other new photoelectric devices,the photoelectric detection effect is further strengthened.PMT achieves high sensitivity detection by photoelectron multiplication,but it features expensiveness,fragility,large size,and high pressure operation,which makes it have limited practical applications.Meanwhile,APDs based on the avalanche effect can generate avalanche current amplification under light excitation,but it is limited by gain,volume,process compatibility,and other factors in practical applications.Single-photon avalanche diode(SPAD)has been applied to various fields such as robotic radar detection,target tracking,and autonomous driving due to its low power consumption,high sensitivity,and low noise characteristics.Most of the SPADs proposed in recent years have high photon detection probability(PDP)under high overbias voltage or enlarge the multiplication region to achieve higher detection probability,but this will affect the junction capacitance and then the time jitter of the device.Thus,we design a SPAD device compatible with most of the processes,which can achieve high PDP at low overbias voltage and has a small dark count rate(DCR).Methods The basic working mechanism of SPAD is characterized by applying technology-computer-aided-design(TCAD)software.Silvaco TCAD software is employed to simulate the device structure and obtain electrical characteristic results from the Atlas Simulator.The Selberrherr model(impact ionization model)built into TCAD software is adopted for analyzing the operating mechanism,and the Newton iteration method is for numerical calculation.Then,a SPAD device with N+/P-well is designed based on a 180 nm standard bipolar CMOS-DMOS(BCD)process,and the device performance is tested by qE-IPCE-K6517B UV detector photoelectric response system and semic

关 键 词：单光子雪崩二极管 光子探测概率 暗计数率 光谱响应 VerilogA模型 

分 类 号：O482.7[理学—固体物理]