Time- and Field-Dependent Trapping in GaN-Based Enhancement-Mode Transistors With p-Gate

This letter describes an extensive analysis of the time- and field-dependent trapping processes that occur in GaN-based gate injection transistors exposed to high drain voltage levels. Results indicate that-even if the devices do not suffer from current collapse-continuous exposure to high drain voltages can induce a remarkable increase in the on-resistance (R
_on
). The increase in R
_on
can be recovered by leaving the device in rest conditions: Temperature-dependent analysis indicates that the activation energy of the detrapping process is equal to 0.47 eV. By time-resolved electroluminescence characterization, we show that this effect is related to the capture of electrons in the gate-drain access region. Finally, we show that charge emission can be significantly accelerated through the injection of holes from the gate.