Ali Yassine is a young scholar specializing in compound semiconductors for power electronic applications. He graduated with a bachelor’s degree in physics in 2018 and a master’s degree in applied physics in 2021 at the University of Freiburg. Currently, Ali is pursuing his PhD at the department of power electronics of the institute of sustainable systems engineering (INATECH) at the University of Freiburg and is conducting research in the topic area "Aluminum Scandium Nitride/Gallium Nitride based power transistors".
Due to its superior physical properties compared to other group III nitrides, aluminum scandium nitride (AlScN) has emerged as a promising candidate for the development of future power electronic applications. The larger piezoelectric response and high spontaneous polarization of AlScN enable a high polarization charge at the interface with gallium nitride (GaN) and thus the accumulation of very high electron sheet charges at the interface. Compared to state-of-the-art aluminum gallium nitride (AlGaN)/GaN-based high-power transistors, AlScN/GaN exhibits a higher transistor current density. In addition, AlScN has a high band gap energy, so that a high critical electric field strength can be expected. By combining the ability to deliver high current densities while operating at high electric fields, AlScN-based devices are predicted to offer higher output power densities compared to current devices, thus achieving the desired improvement in future power electronic devices.