GaN HEMT devices: Experimental results on normally-on, normally-off and cascode configuration

Power electronics systems play key function in power management and motion control: power consumption and volume reduction are strongly required in new applications oriented to protect environment. Moreover, a switching frequency increase is demanded for microwave and power switching applications, thus reducing passive component and converter volume: however, increasing the switching frequency directly increases switching losses. Also, switching applications are very demanding, because semiconductor switches are required to withstand high voltage in reverse condition and handle large current in forward operation mode. New material and new devices are studied to satisfy such requirements, like SiC and GaN devices. In this work, several 600-V class GaN-on-Si HEMT prototypes are presented. These devices have been designed and developed for power switching converter applications. In order to offer a complete scenario of GaN-on-Si HEMT technology, normally-on, normally-off, and cascode-connected devices have been characterized. Achieved experimental results of static and pulsed measurements are then shown.