载流子存储层的厚度和掺杂浓度对碳化硅沟槽栅MOSFET电学特性的影响

he third generation wide band gap semiconductor SiC material has the advantages of high breakdown electric field, high thermal conductivity and high electron saturation rate. It is an ideal material for manufacturing high-power, high-frequency and high-temperature devices. Compared with Si IGBT with the same withstand voltage level, SiC MOSFET has the advantages of low switching loss, high switching frequency and high operating temperature. It has gradually become the preferred switching converter in aerospace, nuclear power plants, new energy vehicles and other fields. Compared with the traditional planar gate SiC MOSFET, the on-resistance of trench gate SiC MOSFET is relatively low. In this paper, based on the basic structure of trench gate SiC MOSFET, using TCAD semiconductor process and device simulation software, the device model of trench gate SiC MOSFET with asymmetric structure with carrier storage layer is established, and the effects of carrier storage layer size and doping concentration on the static and dynamic characteristics of SiC trench gate MOSFET are explored. The set carrier storage layer thickness and doping solubility range from 0.9μm to 3.4μm and 6.0×1015cm-3 to 2.7×1016cm-3, respectively. The simulation results show that when the thickness and doping concentration increase, the specific on resistance and avalanche breakdown voltage of the device decrease, and the switching speed decreases.