@article{oai:nitech.repo.nii.ac.jp:00005093, author = {Arulkumaran, S. and Egawa, Takashi and Ishikawa, H. and Jimbo, Takashi}, issue = {16}, journal = {APPLIED PHYSICS LETTERS}, month = {Oct}, note = {The drain-current collapse at high drain voltage has been studied in AlGaN/GaN high-electron-mobility transistors (HEMTs) on both semi-insulating (SI)-SiC and sapphire substrates using small frequency (120 Hz) sinusoidal wave superimposed dc IDS-VDS characteristics. Low drain-current collapses were observed in AlGaN/GaN HEMTs on SI-SiC substrate when compared with the HEMTs on sapphire substrates. Two and three thermally activated deep traps were observed on SiC-based and sapphire-based HEMTs, respectively. The existence of an additional deep trap (ΔE = 0.61eV) could be associated with the material defects/ dislocations responsible for the severe drain current collapse in sapphire-based HEMTs. The white-light illuminated IDS-VDS characteristics support the existence of more number of deep traps in the sapphire-based HEMTs., application/pdf}, pages = {3073--3075}, title = {Comparative study of drain-current collapse in AlGaN/GaN high-electron-mobility transistors on sapphire and semi-insulating SiC}, volume = {81}, year = {2002} }