250V VDMOS场限环终端的抗单粒子加固研究  

Research on single-event radiation-hardening technology of 250 V VDMOS field limiting ring termination

作　　者：唐新宇 徐海铭[1] 廖远宝 张庆东 TANG Xinyu;XU Haiming;LIAO Yuanbao;ZHANG Qingdong(The 58th Research Institute of China Electronics Technology Group Corporation,Wuxi 214035,China)

机构地区：[1]中国电子科技集团公司第五十八研究所,江苏无锡214035

出　　处：《微电子学与计算机》2025年第1期117-124,共8页Microelectronics & Computer

摘　　要：基于Sentaurus TCAD二维数值仿真方法,对N沟道250 V功率垂直双扩散金属氧化物半导体器件(Vertical Double-diffsed:Metal-Oxide-Semiconductor,VDMOS)的场限环(Field Limit Ring,FLR)终端单粒子烧毁(Single Event Burnout,SEB)机理进行了深入研究。在此基础上,提出了终端缓冲层的加固方案,并通过实验证明了其有效性。FLR终端的SEB最敏感位置在主结与FLR1之间。重离子入射后,产生大量的电子-空穴对,并在漏端电场的加速作用下发生碰撞电离,产生极高的瞬态电流,在局部产生高热引发烧毁。针对FLR终端的单粒子性能提升,提出了缓冲外延层的优化方案。经过仿真验证,缓冲层可以削弱衬底-外延交界处的碰撞电离,降低了重离子入射产生的峰值电流,并缩短电流恢复时间,能够将FLR结构的SEB安全性提升50%以上。对终端缓冲层加固的样品进行118Ta离子实验验证,与普通结构对比,结果证明该结构可以有效降低重离子对终端区的损伤,辐照后IDSS漏电降低4个量级以上。Based on the Sentauus TCAD two-dimensional numerical simulation method,the FLR(Field Limit Ring)terminal single event bunout(SEB)mechanism of N-channel 250 V power VDMOS(Vertical Double-diffused Metal-oxide-Semiconductor)is deeply studied.On this basis,a reinforcement scheme for the termination buffer layer is proposed and its effectiveness is demonstrated through experiments.The most sensitive SEB position of the FLR terminal is between the main junction and FLR1.After the incident of heavy ions,a large number of electron-hole pairs are generated,and collision ionization occurs under the acceleration of the leakage end electric field,resulting in extremely high transient current and local high heat triggering burnout.An optimization scheme for buffer epitaxial layer is proposed to improve the SEB performance of FLR terminals.Simulation results show that the buffer layer can weaken the impact ionization at SUB-EPI interface,reduce the peak current generated by heavy-ion incidence,and shorten the current recovery time,the SEB safety of FLR structure will improved more than 50%.The 118Ta ion experiment of the sample reinforced by the terminal buffer layer is verified.Compared with the common structure,the results show that the structure can effectively reduce the damage of heavy ions to the terminal region,and the IDSS leakage can be reduced by more than 4 orders of magnitude after irradiation.

关 键 词：功率VDMOS 单粒子 结终端 场限环 缓冲层 

分 类 号：TN386.1[电子电信—物理电子学]