Effect of moisture on the frequency-dependent current of an AlGaN/GaN high-electron-mobility transistor

The effect of moisture on the current of an AlGaN/GaN high-electron- mobility transistor was investigated. When the gate voltage was swept from -5 to 0 V at a drain voltage of 7 V, the current decreased with the sweep frequency from 38mA at 0.1 Hz to 15mA at 100 kHz. However, the decrease was mitigated to 29mA by moisturizing the ambient, and a marked current decrease in a pulsed operation was alleviated by moisture from 7.4 to 33mA at 100 kHz with a 10% duty cycle. The binding of polarized H₂O to negatively charged traps was proposed as the reason for the alleviation of the current degradation.