Analysis of deep levels in AlGaN/GaN/Al2O3 heterostructures by CDLTS under a gate pulse

Abstract

Abstract Deep levels behaviors in AlGaN/GaN high electron mobility transistors (HEMTs) with sapphire (Al 2 O 3 ) substrates were characterized by the means of conductance deep level transient spectroscopy (CDLTS) under a gate pulse. Five electron traps have been detected in our sample with activation energy and capture cross-section of 1.3, 1.12, 1.06, 0.22, 0.18 eV and σ n =2.2×10 −12 cm 2 , σ n =2.1×10 −17 cm 2 , σ n =1.5×10 −15 cm 2 , σ n =3.1×10 −15 cm 2 , σ n =5×10 −13 cm 2 , respectively. The nature of the deep traps is discussed.