The comparison between the WBG semiconductors

Abstract

Silicon carbide (SiC) MOSFETs and gallium nitride (GaN) HEMTs, as representative wide-bandgap (WBG) power devices, are accelerating the shift beyond conventional silicon technology by enabling higher efficiency, higher power density, and operation at elevated switching frequencies. This paper provides a comparative assessment of SiC MOSFETs and GaN HEMTs using a set of core performance metrics that are most relevant to practical converter design, including thermal robustness, shortcircuit tolerance, switching speed, and the resulting implications for efficiency and reliability. Drawing on published research and experimental reports from 2022– 2024, the study shows that SiC MOSFETs offer clear advantages in high-temperature stability and short-circuit ruggedness, making them a strong candidate for harsh, high-power operating conditions. In contrast, GaN HEMTs demonstrate superior high-frequency switching capability, supporting compact passive components and high-density converter layouts, but they typically encounter greater reliability challenges under severe electrical and thermal stress. Therefore, device selection should be driven by application requirements: SiC is generally preferable for high-power, high-temperature, and reliability-critical systems, whereas GaN is more suitable for high-frequency, compact, and fast-dynamics power conversion.