Study of Trap Influence on Threshold Voltage of SiC MOSFET Based on Transient Current Method

The threshold voltage shift issue caused by traps in silicon carbide metal-oxide-semiconductor field-effect transistors (SiC MOSFETs) is studied based on transient current method. Experiment results show gate stress, drain stress, and temperature all contribute to threshold voltage shift, with the underlying cause of traps. To obtain physical characteristics of the traps, we test the drain current of the device after filling the traps and utilize a Bayesian iterative deconvolution algorithm to extract the time constants. To accurately explore the impact of traps on the current, we further process the time constant spectrum into a differential amplitude spectrum (DAS), which provides greater precision in addressing the issue of trap amplitudes. We also analyze the variation of trap time constants at different environmental temperatures, and extract the activation energies of the traps in conjunction with the Arrhenius equation. Ultimately, experiments discover two types of electron traps and hole traps.