Analysis of Power Cycle Aging Test for SiC MOSFET

Silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) are gradually replacing silicon (Si)-based devices as the core devices for power conversion in high-temperature, high-pressure, and high-frequency applications due to their superior material properties. The long-term reliability of SiC MOSFETs has become a research focus. Power cycling tests, an important aging test for evaluating device reliability, can reflect the reliability under real working conditions to some extent. The test is conducted using a constant on/off time mode, and the on-state resistance and body diode voltage drop of the devices are measured online during the aging test. The experimental results show that an increase in on-state resistance during power cycling tests causes an increase in junction temperature, which leads to wire bond aging and eventually results in SiC MOSFET failure.