Surge Characteristics of Planar-Gate Silicon Carbide MOSFET in the Third Quadrant

The planar-gate SiC MOSFET exhibits multiple conduction modes when operating in the third quadrant. As the current injection level increases, such as during surge events or other extreme conditions, the conduction characteristics are influenced by both the gate voltage and temperature. To gain a comprehensive understanding of the surge behavior of SiC planar MOSFET in the third quadrant, it is necessary to incorporate temperature calculations to deeply analyze the conduction mechanisms under varying operating conditions and high currents. In this article, experimental methods are used to investigate the surge conduction characteristics of SiC planar MOSFET in the third quadrant, and the surge capability of the device at different gate voltages is evaluated. Furthermore, scanning electron microscopy (SEM) is employed to analyze chip failures, and the mechanisms of surge-induced failure at various gate voltages are summarized. Finally, an electro-thermal coupling model for surge conditions in SiC planar MOSFET in the third quadrant is established. By integrating temperature calculations, the conduction modes under surge conditions are quantitatively analyzed, the results of modeling calculations showing good agreement with experimental data. The findings of this article provide valuable insights into the conduction characteristics and reliability assessment of SiC planar MOSFET in the third quadrant.