Low Output Capacitance 1500V 4H-SiC MOSFETs with 8 mΩ·cm<sup>2</sup> Specific On-Resistance

Abstract

SiC MOSFETs are characterized with a specific on-resistance of 8 m⋅cm2 at room temperature and a blocking voltage of 1500 V. Due to the negative shift in the threshold voltage, devices typically show a reduction in on-resistance with temperature. However, this work shows that a positive resistance temperature coefficient can be achieved by proper device design. SiC MOSFETs were characterized for use in high-frequency resonant converters, where an important switching device figure of merit is the product of the device on-resistance and output capacitance (Ron×Coss). For devices with an active area of 3.6×10-3 cm2, the output capacitance is 12.5 pF at a drain bias of 270V. Thus, these device achieve a resonant converter figure of merit Ron×Coss = 28 ⋅pF at room temperature and 34 ⋅pF at 150°C, better than commercial silicon superjunction devices operating at the same temperatures.