Simulation of Short-Channel Effects in N- and Ga-Polar AlGaN/GaN HEMTs

We have carried out 2-D simulation of N-polar and Ga-polar AlGaN/GaN HEMTs to investigate short-channel effects in highly scaled devices. N-polar HEMTs were found to have better drain-induced barrier lowering (DIBL) suppression than Ga-polar HEMTs. The short-channel effects were found to originate from the 2-D potential distribution in the channel and space-charge-limited current through the buffer. The inverted structure of the N-polar HEMT was found to provide better suppression of short-channel effects under idealized theoretical assumptions that were used in the model presented.