Characterization of n-channel MOSFETs: Electrical measurements and simulation analysis

n-channel 4H-SiC MOSFETs were manufactured and characterized electrically at room temperature by current-voltage and Hall-effect measurements as well as by numerical simulations. To describe the observed electrical characteristics of the SiC MOSFETs, Near-Interface Trap (NIT) and charge carrier mobility degradation models were included in the simulation, performed with Sentaurus Device of Synopsys. For an accurate description of interface defects, their density versus trap energy was extracted from Hall-effect measurements. The result of the extraction indicates a continuous spreading of interface traps in the SiC conduction band, which was not reported before. For the first time also, the interface trap density as a function of trap energy as extracted from Hall-effect measurements was used directly in Sentaurus Device simulations. To check the applicability of the suggested model, it was used for the electrical simulation of MOSFETs with different channel lengths and widths but manufactured using the same technological processes. The developed simulation model shows excellent agreement with experimental results.