IMS-Based GaN Power Module Structure With Low Power Loop Inductance

Switches based on gallium nitride (GaN) offer superior switching speed, low specific on-resistance, and compact dimensions, enabling power converters that exceed efficiencies and power densities of silicon (Si) and/or silicon carbide (SiC) based power converters. Integrating GaN switches into power modules provides an effective approach to fully leverage these advantages, but challenges still exist in minimizing power loop inductance, managing heat dissipation effectively, and achieving cost-effectiveness. To address these challenges, a new power module concept, utilizing an aluminum-base insulated metal substrate (IMS) PCB, is proposed. A $650 ~\mathrm{V} / 60 ~\mathrm{A}, 55 \times 70 ~\text{mm}$ halfbridge module based on this concept was developed and its electrical performance was evaluated through double pulse tests. The inductance of the power loop for the developed module was determined to be $\mathbf{1. 7 5} \mathbf{~ n H}$.