Effective suppression of current collapse in AlGaN/GaN high-electron-mobility transistors

  • Joel Asubar Graduate School of Engineering, University of Fukui
Keywords: Semiconductor, Heterostructures


Gallium nitride (GaN) with its wide bandgap of 3.4 eV is considered as a key semiconductor material for realizing ultra-low-loss power devices. However, GaN-based devices are still plagued by current collapse, which is the temporary reduction of current after application of high voltage and/or power stress, and widely believed to be due to the capture of electrons in traps. Due to the GaN wider band gap, a more extensive variety of traps having longer associated time constants can exist in this material. In addition, the high critical electric field of GaN has facilitated operation up to hundreds of volts for GaN-based devices, leading to extreme charge injection and trapping of carriers. In this work we present some of the measures we are undertaking to combat the current collapse phenomenon towards the widespread acceptance and implementation of GaN-based devices.

About the Speaker

Joel Asubar has held a Senior Assistant Professor position at the Graduate School of Engineering of the University of Fukui since 2014. He obtained his PhD degree in Information Science and Control Engineering from the Nagaoka University of Technology in 2009 with the support of a Monbusho MEXT (Ministry of Education, Culture, Sports, Science and Technology of Japan) Scholarship. He has held postdoctoral positions at the Nagaoka University of Technology (2009-2010) and the Research Center for Integrated Quantum Electronics (RCIQE) at the Hokkaido University (2010-2014). His current research interests include the synthesis of ferromagnetic materials for spintronics applications and the design of state-of-the-art GaN-based transistors.