Simulation Analysis And Design Of A 3.3-kV Reverse-blocking IGBT

Reverse Blocking IGBT(RB-IGBT)is a new type of power device that strengthens the PN junction on the back side of the IGBT.Direct use of RB-IGBTs has the advantages of reduced total on-state voltage,low cost,low total power consumption,high reliability and robustness compared to conventional IGBT series diode applications.High-voltage reverse-resistance IGBTs have been widely used in power grid,rail transit,and electro-chemical industries.Since their introduction,RB-IGBTs have been continuously improved in processing technology and structural design,and their performance has been continuously improved,making RB-IGBTs more Broad application prospects.This paper focuses on designing a high-voltage reverse-resistance IGBT,and the forward and reverse voltage withstand voltage can reach more than 4000 V.The model and simulation of the reverse-resistance IGBT are carried out by using the Sentaurus TCAD simulation software.The design principle of the device cell and terminal region is described,and the structure is analyzed.The influence of parameters on the performance of the device finally gives more reasonable design parameters.The specific work contents are as follows:1)For the cell part,the cell structure,the resistivity of the substrate material,the active region,and the structure parameters of the collector region were designed and verified.The embedding N+ region implant dose and junction depth of the cell were determined by simulation analysis.Well implant dose and junction depth,gate length,substrate thickness and doping concentration,P-back region thickness and implant dose.The blocking characteristics,static characteristics and switching characteristics of the 3.3kV cell structure design are simulated.2)For the terminal area,the forward voltage terminal structure is designed: including the number of field limiting rings,the width of the field limiting ring,the spacing between the field limiting rings,the length of the field plate,etc.,and the discussion field is analyzed through simulation.The effect of limiting ring doping concentration and junction depth on forward withstand voltage;For the reverse voltage structure of the terminal area: a new type of high-efficiency perforated isolation terminal structure is proposed.Compared with the traditional RB-IGBT diffusion isolation terminal,the isolation terminal can save about 80% of the terminal area and at the fixed terminal area.To maximize the reverse withstand voltage of RB-IGBT,this paper proposes an N+ blocking ring structure in the terminal area.This structure can be increased to the same withstand voltage without adding a barrier ring.This design can save 30% terminal area.