Deep traps analysis in AlGaN/GaN heterostructure transistors

Abstract

AlGaN/GaN high electron mobility transistors are investigated by DLTS measurements. 6 different are extracted with the following activation energies: 0.12 eV, 0.15 eV, 0.21 eV, 0.42 eV, 0.49 eV and 0.94 eV. Based on comparison with literature results and measurements as a function of the pulse reverse bias, the trap localisation in the structure is discussed. Additional measurements as a function of the filling pulse duration reveal the presence of decorated extended defects in the samples. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Deep traps in GaN-based structures as affecting the performance of GaN devices

“…In Ref. [271] DLTS measurements were performed on Schottky diodes of test FET structures prepared on MOCVD-grown AlGaN/GaN. The authors observed a measurable hysteresis of C-V characteristics at low temperatures, but no strong shift of the threshold voltage of the type described by Figs.…”

Low- and high-frequency capacitance of aluminum gallium nitride/gallium nitride heterostructures with interface traps

“…We assumed two types of deep traps at the interfaceacceptor type and donor type traps [18][19][20]. Acceptor type traps are neutral when they are empty and negative when they are occupied by electron.…”

“…Since this charge has large time constants the transistor properties are time dependent which also influences their stability. According to experimental results these traps are prevalently concentrated at the AlGaN and GaN layers interface [1][2][3], but also in AlGaN or in GaN layer [4]. Interface traps are also a reason for capacitance hysteresis in AlGaN/GaN heterostructures [5].…”

Analyses of hetero-interface trapping properties in AlGaN/GaN high electron mobility transistor heterostructures grown on silicon with thick buffer layers

“…The presence of extended defects due to dislocations mostly located at the AlGaN/GaN hetero-interface was also confirmed by Fourier Transform (FT-DLTS) technique. 21 Therefore, good quality MOCVD AlGaN/GaN HEMT heterostructures were grown using thick buffer layers with reduced D D-edge as observed from the XRC results as well as smoother interface with low D it-min value as evident from improved carrier transport properties.…”