Research on junction temperature of SiC MOSFET module

Abstract

Silicon carbide (SiC)-based wide-bandgap semiconductor devices such as metal-oxide-semiconductor field-effect transistors (MOSFETs) generate large amounts of heat because of their small size and increasingly high power density. The junction temperature is the most important index for evaluation of the reliability of these devices. This article proposes a method to study the changes in the forward voltage across the drain (D)-source (S) junction (VDS) under various test conditions from the perspectives of temperature sensitivity, stability, repeatability, and anti-interference properties, with the aim of determining suitable temperature test conditions for SiC MOSFET chips to achieve precise device temperature measurements. The accuracy of the proposed measurement method is verified via comparison with an infrared thermal imaging method and an electrical method. The results obtained show that the error in the SiC MOSFET junction temperature (Tj) measurements when compared with the infrared method and the electrical method is around 1%.