Study On 1200V Trench Field Stop Insulated Gate Bipolar Transistor(IGBT)

IGBT combines the advantages of MOSFET and GTR devices.That is,small driving power and lower saturation voltage.It is suitable for the converter system with DC voltage of 600 V and above.It is also widely used in strategic industries such as rail transportation,ship drive,smart grid,power electronics,new energy vehicles and other strategic industries.Based on current IGBT technology platform and current company process,The description is expanded around the research and development work of 1200 V trench FS IGBT.Including the terminal structure design and active cell design.Using TCAD software,simulated and analysised the terminal structure,and device field stop layer of different process design scheme.Design and verification results of IGBT device and process design,and performance testing device of different design scheme under static and dynamic and safe work area,preliminary the following conclusions are obtained:1.TCAD software simulation results show that the terminal structure of the combination of multi field limiting ring and the field plate structure can achieve higher breakdown voltage,and has smaller dose effect of field limiting ring injection;A field stop layer can be formed by ion implantation or epitaxial growth,and simulation result show that these two way can get BV demand.But it is necessary to optimize the field stop layer's concentration to get low saturation voltage.2.Experiment data show tha the design of combination of active cell and dummy cell can reduce MOS region channel width of the top of the IGBT,thereby reduce the short-circuit current,which improved the safe operation area.At the same time,dummy cell can reduce saturation voltage by enhancing the cellular carrier concentration at the top MOS region.Experiment data show that using the epitaxial layer,and collector injection at the dose of 5e13,the device can achieve follow result: BV 1640 V,Vdson1.42 V at 20 A,Vdson 2.32 V at 40 A,short circuit time 19 us at 600 V.The comparison of different experimental conditions show that,IGBT can get lower the switching loss,much wide short circuit safe operating area and low saturation voltage and high breakdown voltage by using epitaxial regrowth.