
Gallium nitride (GaN) power devices are gaining traction in electrified transportation due to their low switching losses, high-frequency capability, and compact footprint, enabling higher efficiency and power density than conventional silicon (Si) and silicon carbide (SiC) technologies. However, their large-scale adoption, especially in main powertrains, remains limited by insufficient voltage and current ratings as well as an incomplete understanding of device reliability under stressful operating conditions. Here, we review recent advances in GaN devices for transportation electrification. We first examine the industrial multilevel framework of device reliability qualification for automotive applications, aiming to better inform device researchers of application requirements. We then survey recent GaN device innovations targeting higher voltages and improved robustness. We also discuss monolithic bidirectional switches …