Design Of Bidirectional CSTBT

Power electronics technology is the technology of power conversion and control,widely used in power systems,electrical devices and a variety of traditional power equipment.The essence of power electronic transformation is to use the switching function of electronic power devices to achieve the weak point of strong power control.As the basis of power electronics technology,electronic power devices are also the core components of power electronic conversion devices more and more concerned by society.Insulated Gate Bipolar Transistor(IGBT)as a kind of electronic power devices,is widely used in the field of high pressure due to its high input impedance,easy measurement,a wide range of switching frequency etc.The bidirectional IGBT as a new type of power devices is always used in the AC rectification circuit and matrix converter,achieving the integration of the device.This article first introduces the development of IGBTs and bidirectional IGBTs,and then describes the working principle of bidirectional IGBTs.First of all,the basic structure of bidirectional IGBT is proposed.Secondly,the basic structure of the bidirectional IGBT is described in terms of threshold voltage,blocking characteristics,four working modes,turn-off characteristics and reverse recovery.Finally,Trade-off between turn-off losses and conduction losses is described,and briefly describes some commonly used methods for reducing turn-off losses such as anodic emission efficiency control and lifetime control techniques.This paper proposes a bidirectional CSTBT device with P-type buried layer on the basis of traditional bidirectional IGBT.Compared with the traditional bidirectional IGBT,the device has better carrier distribution in the drift region and shields the electric field,so that it has a better compromise between the forward voltage drop and the turn-off loss.The optimized bidirectional CSTBT has a 1304V withstand voltage,1.04V@150A/cm~2 forward voltage drop,25mJ turn-off loss and good trade-off between forward voltage drop and turn-off loss,meeting design requirements.