Identifying the Traps in the Channel Region in GaN-Based HEMTs Using a Nonmonotone Drain Current Transient

The reliability of GaN-based high-electron mobility transistors (HEMTs) is still hindered by trapping effects. Current transient spectroscopy provides an effective way to characterize traps. In this paper, we revealed a trapping behavior hidden in the recovery transients caused by the measuring voltage, and for the first time, we took advantage of it to demonstrate the
${I} _{\mathrm{ ds}}$
-related traps in these devices. We applied this method to three different HEMTs and demonstrated traps’ energy levels using Arrhenius plots. In particular, we found that the
${I} _{\mathrm{ ds}}$
-related traps in different HEMTs had different temperature dependences. A perfect exponential relationship between the degradation rate and the channel current in the linear region was identified. This method provides an effective and easy way to localize traps that capture electrons from the 2-D electron gas directly.