界面陷阱分布对SiC MOSFET准静态C-V特性的影响  

Effect of Interface Trap Distribution on Quasi-Static C-V Characteristic of SiC MOSFETs

作　　者：高秀秀 王勇志 胡兴豪 周维 刘洪伟 戴小平 Gao Xiuxiu;Wang Yongzhi;Hu Xinghao;Zhou Wei;Liu Hongwei;Dai Xiaoping(Coresing Semiconductor Technology Co.,Ltd.,Zhuzhou 412001,China)

机构地区：[1]湖南国芯半导体科技有限公司,湖南株洲412001

出　　处：《半导体技术》2023年第4期294-300,323,共8页Semiconductor Technology

基　　金：国家科技助力经济2020重点专项(2020YFF0426582)。

摘　　要：为了分析4H-SiC/SiO_(2)固定电荷和界面陷阱对MOSFET准静态电容-电压(C-V)特性曲线的影响机制,对不同栅氧氮退火条件下的n沟道4H-SiC双注入MOSFET(DIMOSFET)进行了氧化层中可动离子、界面陷阱分布和准静态C-V特性曲线的测试,并结合仿真探讨了测试频率、固定电荷、4H-SiC/SiO_(2)界面陷阱分布对准静态C-V特性曲线的影响。实验和仿真结果表明:电子和空穴界面陷阱分别影响准静态C-V曲线的右半部分和左半部分;界面陷阱的E0、Es、N0(E0为陷阱能级中心与导带底能级或价带顶能级之差,Es为陷阱能级分布的宽度,N0为陷阱能级分布的密度峰值)对准静态C-V曲线的影响是综合的;当E0为0 eV,Es为0.2 eV,电子和空穴捕获截面均为1×10^(-18) cm^(2),电子和空穴界面陷阱的N0分别为5×10^(12) eV^(-1)·cm^(-2)和2×10^(12) eV^(-1)·cm^(-2)时,4H-SiC DIMOSFET准静态C-V仿真曲线和实测曲线相近。To analyze the effect mechanism of fixed charges and interface traps of 4H-SiC/SiO_(2) on the quasi-static C-V characteristic of MOSFET,mobile ions in oxide layer,interface traps distribution,quasi-static C-V characteristic curves of n-channel 4H-SiC double implant MOSFETs(DIMOSFETs)under different gate oxidation nitrogen annealing conditions were tested,and the effects of testing frequency,fixed charges,4H-SiC/SiO_(2) interface trap distribution on quasi-static C-V characteristic curves were discussed by simulation.The experiment and simulated results show that the electron and hole interface traps affect the right side and left side of quasi-static C-V curves,respectively.E0,Es,N0(E0 is the difference between the central energy level of the trap distribution and the bottom energy level of the conduction band or the top energy level of the valence band,Es is the width of trap energy level distribution,N0 is the peak density of trap energy level distribution)of interface traps have a comprehensive influence on quasi-static C-V curves.The simulated quasi-static C-V curve of 4H-SiC DIMOSFET is close to the tested result when E0 is 0 eV,Es is 0.2 eV,hole and electron capture cross sections are both 1×10^(-18) cm^(2),and N0 of electron and hole interface traps are 5×10^(12) eV^(-1)·cm^(-2) and 2×10^(12) eV^(-1)·cm^(-2),respectively.

关 键 词：4H-SIC 双注入MOSFET(DIMOSFET) 界面陷阱 准静态电容-电压(C-V)特性 可动离子 

分 类 号：TN386.1[电子电信—物理电子学]