Small current collapse in AlGaN/GaN HFETs on a‐plane GaN self‐standing substrate

Autor: Masahito Yamaguchi, Motoaki Iwaya, Yasuhiro Isobe, Takayuki Sugiyama, Y. Mori, Isamu Akasaki, S. Kamiyama, Yoshio Honda, Yasuo Kitaoka, Mamoru Imade, Hiroshi Amano, Tetsuya Takeuchi
Rok vydání: 2012
Předmět:
Zdroj: physica status solidi c. 9:875-878
ISSN: 1610-1642
1862-6351
DOI: 10.1002/pssc.201100397
Popis: We measured drain bias stress effects and current collapse in AlGaN/ GaN heterostructure field-effect transistors (HFETs) on a-plane and c-plane GaN substrates. An a-plane AlGaN/GaN HFET (a-HFET) shows small current collapse with a threshold voltage (Vth = -1.8 V). On the other hand, a c-plane HFET (c-HFET) with the same barrier thickness (20 nm) shows a small current collapse, although Vth was negatively large (Vth = -4 V). Current collapse in a-HFET was not large compared with that in conventional c-HFET on GaN. A c-HFET on sapphire was also measured. The current collapses in HFETs on sapphire were larger than that in HFETs on a GaN substrate. The current collapses in the thin-barrier c-HFET (Vth = -1.8 V) were particularly large. Therefore, an a-plane device is promising for a small or positive Vth with small current collapse. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Databáze: OpenAIRE
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