Drain-Voltage-Induced Secondary Effects in AlGaN/GaN HEMTs With Integrated Body-Diode

Integration of body-diode-based back-gate control in AlGaN/GaN high-electron mobility transistors (HEMTs) was recently demonstrated by the authors to enable dynamic control of the device characteristics. Here, we present an experimental study of drain-voltage-induced secondary effects in AlGaN/GaN HEMTs with integrated body-diode. Both the three-terminal and four-terminal device characteristics are studied to understand the secondary effects in this configuration. The results show that the voltage at the drain terminal plays a crucial role in biasing the body-diode under dynamic operation. Drain-voltage-induced dynamic biasing of the body-diode is observed both under the biased and floating back-gate conditions. The kink-effect in the saturation channel current and light emission at the source terminal are observed at higher drain voltages. Our results show that a combination of high resistivity of the p-GaN layer and the direct bandgap nature of III-nitride (III-N) material prevents the parasitic bipolar junction transistor (BJT)-triggered latch-up mechanism in this device structure.