Document Type
Article
Original Publication Date
2007
Journal/Book/Conference Title
Applied Physics Letters
Volume
91
Issue
26
DOI of Original Publication
10.1063/1.2824461
Date of Submission
April 2015
Abstract
InGaN possesses higher electron mobility and velocity than GaN, and therefore is expected to lead to relatively better performances for heterostructure field effect transistors (HFETs). However, the reported mobilities for AlGaN∕InGaNHFETs are lower than GaN channel HFETs. To address this issue, we studied the effect of different barriers on the Hall mobility for InGaN channel HFETs grown by metal organic chemical vapor deposition. Unlike the conventional AlGaN barrier, the AlInN barrier can be grown at the same temperature as the InGaN channel layer, alleviating some of the technological roadblocks. Specifically, this avoids possible degradation of the thin InGaN channel during AlGaN growth at high temperatures; and paves the way for better interfaces. An undoped In0.18Al0.82N∕AlN∕In0.04Ga0.96NHFET structure exhibited a μH=820cm2/Vs, with a ns=2.12×1013cm−2 at room temperature. Moreover, with an In-doped AlGaN barrier, namely, Al0.24In0.01Ga0.75N, grown at 900°C, the μH increased to 1230cm2/Vs with a ns of 1.09×1013cm−2 for a similar InGaN channel. Furthermore, when the barrier was replaced by Al0.25Ga0.75N grown at 1030°C, μH dropped to 870cm2/Vs with ns of 1.26×1013cm−2 at room temperature. Our results suggest that to fully realize the potential of the InGaN channel HFETs, AlInN or AlInGaN should be used as the barrier instead of the conventional AlGaN barrier.
Rights
Xie, J., Leach, J.H., Ni, X., et al. Electron mobility in InGaN channel heterostructure field effect transistor structures with different barriers. Applied Physics Letters, 91, 262102 (2007). Copyright © 2007 AIP Publishing LLC.
Is Part Of
VCU Electrical and Computer Engineering Publications
Comments
Originally published at http://dx.doi.org/10.1063/1.2824461