Deep levels and nonlinear characterization of AlGaN/GaN HEMTs on silicon carbide substrate

Deep levels in AlGaN/GaN high electron mobility transistors (HEMTs) on SiC substrate are known to be responsible for trapping processes like: threshold voltage shift, leakage current, degradation current, kink effect and hysteresis effect. The related deep levels are directly characterized by conductance deep level transient spectroscopy (CDLTS) method. Hereby, we have detected five carrier traps with activation energy ranging from 0.84 to 0.07 eV. In this study, we have revealed the presence of two hole-like traps (HL1 and HL2) observed for the first time by CDLTS with activations energy of 0.40 and 0.84 eV. The localisation and the identification of these traps are presented. Finally, the correlation between the anomalies observed on output and defects is discussed.