A New Extraction Method of SiC Power MOSFET Threshold Voltage using a Physical Approach

The threshold voltage Vth is an important device parameter for the design, characterization, modeling and simulation of Silicon Carbide (SiC) Metal Oxide Semiconductor Field Effect Transistors (MOSFETs), which are exploited in the new generation of energy conversion systems. The reduction of the threshold voltage increases the performance in terms of switching time for the power inverter. The study of the evolution of its value over time must be considered by the designers of the systems. In this paper, we propose a method to extract the parameter Vth based on a physical approach, involving the static I-V measurements and the use of the Levenberg-Marquardt optimization algorithm. We focus our studies on the physical definition of the threshold voltage, then we develop a new procedure and we describe four extraction methods often used to obtain the accurate values of threshold voltage. The study is carried out on commercial components, we compare the threshold voltage values found from the measurements performed on a power SiC-MOSFETs for two generations of CREE constructor.