一种低功耗4H-SiC IGBT的仿真研究  

Simulation Study of a Low Power 4H-SiC IGBT

作　　者：苏芳文 毛鸿凯 隋金池 林茂 张飞 SU Fangwen;MAO Hongkai;SUI Jinchi;LIN Mao;ZHANG Fei(School of Electronics and Information Engineering,Hangzhou Dianzi University,Hangzhou 310018,China)

机构地区：[1]杭州电子科技大学电子信息学院,浙江杭州310018

出　　处：《电子科技》2021年第1期31-35,59,共6页Electronic Science and Technology

基　　金：浙江省杰出青年基金(LR17F040001)。

摘　　要：针对传统沟槽栅4H-SiC IGBT关断时间长且关断能量损耗高的问题,文中利用Silvaco TCAD设计并仿真了一种新型沟槽栅4H-SiC IGBT结构。通过在传统沟槽栅4H-SiC IGBT结构基础上进行改进,在N+缓冲层中引入两组高掺杂浓度P区和N区,提高了N+缓冲层施主浓度,折中了器件正向压降与关断能量损耗。在器件关断过程中,N+缓冲层中处于反向偏置状态的PN结对N-漂移区中电场分布起到优化作用,加速了N-漂移区中电子抽取,在缩短器件关断时间和降低关断能量损耗的同时提升了击穿电压。Silvaco TCAD仿真结果显示,新型沟槽栅4H-SiC IGBT击穿电压为16 kV,在15 kV的耐压设计指标下,关断能量损耗低至4.63 mJ,相比传统结构降低了40.41%。In this paper,a new trench gate 4H-SiC IGBT structure is designed and simulated by Silvaco TCAD for the problem that the traditional trench gate 4H-SiC IGBT has long turn-off time and high turn-off energy loss.By improving the structure of the conventional trench gate 4H-SiC IGBT,two sets of high doping P and N layers are introduced in the N buffer layer to increase the donor concentration of the N buffer layer,which compromises the forward voltage drop of the device and turn off the energy loss.The PN junction in the reverse bias state in the N buffer layer optimizes the electric field distribution in the Ndrift region when the device is in the turn-off process,which accelerates the electron extraction in the Ndrift region and shortenes the turn-off time of the device.This ultimately reduces the turn-off energy loss of the device and increases the breakdown voltage of the device.Silvaco TCAD simulation results show that the new trench gate 4H-SiC IGBT has a breakdown voltage of 16 kV.Compared with the conventional structure with a breakdown voltage of 15 kV,the turn-off energy loss is as low as 4.63 mJ,which is 40.41%lower than the conventional structure.

关 键 词：4H-SIC IGBT 击穿电压 关断能量损耗 正向压降 Silvaco TCAD 

分 类 号：TN312+.3[电子电信—物理电子学]