Dynamic Behavior of Threshold Voltage and I D – V DS Kink in AlGaN/GaN HEMTs Due to Poole–Frenkel Effect

The kink effect in field-effect transistors (FETs) consists in a sudden increase in drain current, I₃, during a drain voltage sweep and leading to a higherI₃saturation value. We report new experimental data concerning the dynamic behavior of the “kink” in AlGaN/GaN HEMTs and correlate them with deep levels. The results demonstrate the role of the Poole–Frenkel effect in determining the occurrence of the kink and identify the experimental conditions that make it observable.