A Hybrid 3.3 kV 450 A Half-bridge IGBT Power Module with SiC Schottky Diodes

This work presents a hybrid 3.3 kV/450 A insulated-gate bipolar transistor (IGBT) power module, utilising the half-bridge topology. In contrast to the traditional fashion, each IGBT chip in this module is allocated with two anti-parallel silicon carbide (SiC) Schottky barrier diodes (SBDs). Each SBD describes smaller footprint than the conventionally used silicone (Si) based fast recovery diode at this voltage and current level. By adopting smaller SiC SBDs in this hybrid-style packaging structure, the SBD chip yield can be greatly improved, without any additional fabrication cost. To benchmark the advantages of this hybrid power module over the Si-based counterpart, both power modules are designed, fabricated as well as tested statically and dynamically. It is shown that while both types show similar thermal behaviour, the hybrid power module describes much lower IGBT turn-on current overshooting, diode reverse recovery loss and IGBT turn-on loss. Based on the measured results, the power losses of both modules under a three-phase inverter operation condition are calculated, showing that the hybrid module has considerably lower power losses and junction temperature rise.