Impact of channel thickness scaling on the performance of GaN-on-Si RF HEMTs on highly C-doped GaN buffer

Impact of channel thickness scaling on the performance of GaN-on-Si RF HEMTs on highly C-doped GaN buffer ■

Alireza Alian, Alireza Alian, Alireza Alian, Raul Rodriguez, Raul Rodriguez, Raul Rodriguez, Sachin Yadav, Sachin Yadav, Sachin Yadav, Uthayasankaran Peralagu, Uthayasankaran Peralagu, Uthayasankaran Peralagu, Arturo Sibaja-Hernandez, Arturo Sibaja-Hernandez, Arturo Sibaja-Hernandez, Vamsi Putcha, Vamsi Putcha, Vamsi Putcha, Ming Zhao, Ming Zhao, Ming Zhao, Rana Yasser ElKashlan, Rana Yasser ElKashlan, Rana Yasser ElKashlan, Bjorn Vermeersch, Bjorn Vermeersch, Bjorn Vermeersch, Hao Yu, Hao Yu, Hao Yu, Erik Bury, Erik Bury, Erik Bury, Ahmad Khaled, Ahmad Khaled, Ahmad Khaled, Nadine Collaert, Nadine Collaert, Nadine Collaert, Bertrand Parvais, Bertrand Parvais, Bertrand Parvais

Abstract ■

This work investigates scaling of the GaN channel thickness on top of a carbon-doped GaN buffer (cGaN) grown on 200mm Si substrates. Device performance tradeoffs are analyzed in terms of DC, RF, reliability and thermal behavior. A thinner channel improves DIBL, Ioff,Vth roll-off and degrades fT,fmax , PAE, Pout, charge trapping and thermal conductance characteristics. Transconductance was observed to increase under high saturation drain bias for thin and short channels indicating the lateral device scaling potential of cGaN based HEMTs.