Wide-Bandgap Power Semiconductors: Key Components to Save Our Planet

Power semiconductors are key enablers for highly efficient power conversion to address our global societal challenges. Silicon-based power devices have dominated the field for the past four decades with thyristors, power MOSFETs, diodes, and IGBTs. However, these devices are slowly but surely reaching the material limits of silicon, namely its maximum electric field strength due to the small bandgap. Wide-bandgap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) allow the silicon limit to be overcome with a tenfold increase in the critical electric field. We present the main SiC and GaN device concepts and their technological implementations. We compare their performance with best-in-class silicon devices for the most important power electronics topologies. Finally, we will show the benefits of these new devices for some real-world use cases, such as a 10-kW photovoltaic inverter with a record efficiency of 99.4%.