Investigation of the dynamic on-state resistance of AlGaN/GaN HEMTs

The dynamic on-state resistance (R-ON) increase in AlGaN/GaN high-electron-mobility transistors (HEMTs) has been investigated by pulsed I-V measurements on devices issued from UMS GaN technology. We have studied the influence of the measurement setup on the pulsed I-V measurements and highlighted the importance of the I-DS(t) waveforms to verify the validity of the measurements. The R-ON is not sensitive to short time transients below 10 mu s as well as for fresh and HTRB aged devices. The dynamic resistance (R-ON) is doubled in off-state conditions by increasing V-DS0 from 0 V to 50 V. The threshold voltage V-TH of aged devices has not shifted during the HTRB aging test carried out for 2200 h. Therefore, trapping effects responsible for the increase of R-ON are rather more located in the gate-source and drain-source access regions than under the gate. (C) 2015 Published by Elsevier Ltd.