Comprehensive Analysis of Deep level Effects and in-situ Photoionization in 0.15 $\mu \mathrm{m}$ buffer-free AIGaN/GaN HEMTs for RF applications

De-trapping mechanisms and their dependence on applied bias have been studied in RF buffer-free AIGaN/GaN HEMTs on SiC. De-trapping time decreases by several orders of magnitude when the device is biased. The role of electroluminescence radiation emitted by the device in promoting in-situ trap photoionization is discussed.