18 kV 4H-SiC ESC-IGBT结构设计与特性研究  

Structure design and characteristics research of 18kV 4H⁃SiC ESC⁃IGBT

作　　者：张莉 陈致宇 ZHANG Li;CHEN Zhiyu(The 29th Research Institute of China Electronics Technology Group Corporation,Sichuan Research Center of High Efficiency Power Conversion Technology Engineering,Chengdu 610036,China)

机构地区：[1]中国电子科技集团公司第二十九研究所、四川省高效电源变换技术工程研究中心,四川成都610036

出　　处：《现代电子技术》2023年第18期47-52,共6页Modern Electronics Technique

摘　　要：针对碳化硅(SiC)绝缘栅双极晶体管(IGBT)空穴抽取慢,导致关断损耗高的问题,文中提出一种发射极肖特基接触的18 kV 4H-SiC IGBT(ESC-IGBT)新结构。该结构在JFET区上方引入肖特基结,并将其与发射极短接,提供额外的空穴抽取路径,降低关断损耗。当ESC-IGBT处于关断阶段时,随着耗尽层在漂移区中扩展,额外的空穴抽取路径开始工作,可以有效解决单一路径空穴抽取慢的问题,进而降低关断损耗。Sentaurus TCAD分析结果表明:ESC-IGBT击穿电压为20.9 kV时,所提出的ESC-IGBT的栅氧化层电场相比传统平面型有效降低46%,栅氧可靠性有所提高;在正向导通特性无明显退化的前提下,ESC-IGBT栅集电荷比传统平面型SiC IGBT结构降低37%,关断损耗和工业优值(IFOM=V_(ce)·E_(off))降低34%。另外,ESC-IGBT易实现的工艺与主流SiC IGBT工艺兼容,适用于高频高可靠性电力电子系统。In allusion to the problem that the hole extraction of SiC(silicon carbide)IGBT(insulated gate bipolar transistor)is slow,which leads to high turn off loss,a new 18 kV 4H-SiC emitter Schottky contact IGBT(ESC-IGBT)structure is proposed.In this structure,a Schottky junction is introduced to above the JFET region,and shorted to the emitter,so as to provide additional hole extraction path and reduce turn off loss.When ESC-IGBT is in the turn off phase,additional hole extraction path can start to work with the Depletion region expanding in the drift region,which can effectively solve the problem of slow hole extraction in a single path,thus reducing the turn off loss.Sentaurus TCAD analysis results show that the breakdown voltage of the ESC-IGBT is 20.9 kV,the electric field of the proposed ESC-IGBT Gate oxide is effectively reduced by 46%compared with the traditional planar type,and the reliability of the gate oxide is improved.Under the premise of no significant degradation of forward conduction characteristics,the charge collection of the ESC-IGBT gate is reduced by 37%compared to the traditional planar SiC IGBT structure,and the turn-off loss and industrial optimal value(IFOM=V_(ce)·E_(off))are decreased by 34%.The easy to implement process of ESC-IGBT is compatible with mainstream SiC IGBT process,and is suitable for high-frequency and high reliability power electronic systems.

关 键 词：ESC-IGBT SiC IGBT 空穴抽取路径 肖特基接触工艺 栅氧可靠性 关断损耗 

分 类 号：TN322.8-34[电子电信—物理电子学]