Design And Optimization Of A Novel 3300V Planar Gate IGBT

High-voltage insulated gate bipolar transistor(IGBT)is widely used in medium and high-voltage applications such as rail transportation,smart grids and large ships with the advantages of high blocking voltage,fast switching and high current,and becomes a hot research topic in the industry.With the advantages of low saturation current,high short-circuit capability and low gate capacitance,planar gate IGBT becomes one of the mainstream structures of high-voltage IGBT.IGBT chips contain a cell area and a terminal area,of which the cell area determines the current capability of the chip and the terminal area is a special structure set up to improve the breakdown characteristics.In order to further reduce the on-state voltage drop of high-voltage planar gate IGBTs and increase the chip power density,this thesis carries out research on new 3300V planar gate IGBTs from two aspects:cell structure and terminal structure,respectively,with the following main work.1.For the cell,a novel three-dimensional dual injection enhanced planar gate IGBT(DIE-PIGBT)is proposed.Based on a conventional planar gate IGBT structure with a shielded trench(Con-IGBT),the DIE-PIGBT introduces a P-type floating region,which improves the relationship between N-type carrier storage layer concentration and breakdown voltage(BV),resulting in lower on-state voltage drop(V_ceon)and saturation current(I_sat).The structure also has a self-Adaptive hole path,allowing for lower turn-off loss(E_off).The simulation results show that the on-state voltage of the DIE-PIGBT is reduced by 31.0%compared to the Con-PIGBT,and the on-state voltage of the DIE-PIGBT.Pro with the same BV with Con-PIGBT is reduced by 33.8%compared to the Con-PIGBT,and by 4.4%compared to the DIE-PIGBT.At the same on-state voltage=2.51V,the turn-off loss of the DIE-PIGBT is reduced by 44%compared to the Con-PIGBT and the turn-off loss of the DIE-PIGBT.Pro is reduced by 49.1%compared to the Con-PIGBT and by 9.2%compared to the DIE-PIGBT.At the gate voltage of 15V,the saturation current of the DIE-PIGBT is reduced by 40.5%compared to the Con-PIGBT,and the short-circuit withstand time is 1.9 times longer than that of the Con-PIGBT.2.For the terminal,a single-injection multi-zone junction terminal extension(JTE)structure is proposed,and a study of the JTE ion implantation mask model is carried out.The factors affecting the breakdown voltage of the JTE terminal are then investigated,such as injection dose,energy,push-junction time,interface charge,temperature and mask plate variation.The proposed multi-zone JTE termination structure has a smaller area and improves the sensitivity of the breakdown voltage to the injection dose,increasing the process tolerance.Simulation results show that the breakdown voltage of the terminal exceeds 4000 V when the injected dose is in the range of 3×10¹²cm^-2 to7×10¹²cm^-2,meeting the blocking voltage requirement.Compared with the conventional single-zone JTE terminal structure,the multi-zone JTE terminal has a wider process window and a higher chip power density with the same blocking capability.Based on the above simulation,the terminal layout design with large chamfered corners was carried out and put into flow experiments.