3300 V-FS-IGBT击穿特性及其相关工艺的研究

The Research on Breakdown Characteristics and Corresponding Process of 3 300V-FS-IGBT

对于3300 V高压绝缘栅双极型晶体管(Insulated Gate Bipolar Transistor,IGBT)器件,因其衬底电阻率非常高,在场限环、场板、场限环+场板、结终端扩展(Junction Termination Extension,JTE)、横向变掺杂(Variation of Lateral Doping,VLD)、场限环+多级场板等众多提升耐压的方案中,场限环+多级场板是最切实可靠的方案。基于现有的3300 V场截止型(FS)IGBT平面工艺制造平台,采用场限环+多级场板结终端结构,TCAD(Technology Computer Aided Design)仿真发现场板厚度的增加,其击穿电压也随之增大。将此TCAD仿真设计方案通过不同场板厚度分组试验进行流片验证,击穿电压大于3300 V。但随着场板厚度增加,其翘曲度也跟着相应增加,为此进行了正反面膜质淀积后回流工艺优化,翘曲度显著减少,与场板厚度弱相关,满足了设计要求,实测值与仿真值相吻合。

For 3300 V high voltage IGBT device,due to extremely high resistance of substrate,among those enhancing breakdown voltage terminal solution such as floating field ring,field plate,floating field ring plus field plate,JTE,VLD and floating field rings plus multistep field plates,floating field rings plus multistep field plates is the most feasible one.Based on the existing planar 3300 V field stop(FS)IGBT platform,adopting floating field rings plus multistep field plates’terminal structure,the TCAD simulation shows that the breakdown voltage increases while the thickness of field plate increase.This TCAD simulation scheme is fabricated in process through the field plate thickness DOE(Design of Experiment),3300 V breakdown voltage is achieved.But as the thickness increase,the bow also increases accordingly,so the frontside and backside film deposition reflow optimization is carried out,the bow reduces significantly,which has weak relation with the thickness,meets the design requirement.The measured breakdown voltage result verified the TCAD simulation.