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Title: Degradation and annealing effects caused by oxygen in AlGaN/GaN high electron mobility transistors

Abstract

Hot-carrier degradation and room-temperature annealing effects are investigated in unpassivated ammonia-rich AlGaN/GaN high electron mobility transistors. Devices exhibit a fast recovery when annealed after hot carrier stress with all pins grounded. The recovered peak transconductance can exceed the original value, an effect that is not observed in control passivated samples. Density functional theory calculations suggest that dehydrogenation of pre-existing O{sub N}-H defects in AlGaN plays a significant role in the observed hot carrier degradation, and the resulting bare O{sub N} can naturally account for the “super-recovery” in the peak transconductance.

Authors:
; ; ; ;  [1];  [2];  [3];  [1];  [3]; ; ;  [4];  [2];  [3]
  1. Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennesse 37235 (United States)
  2. Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennesse 37235 (United States)
  3. (United States)
  4. Materials Department, University of California, Santa Barbara, California 93106 (United States)
Publication Date:
OSTI Identifier:
22590614
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 2; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AMMONIA; ANNEALING; DEHYDROGENATION; DENSITY FUNCTIONAL METHOD; ELECTRON MOBILITY; GALLIUM NITRIDES; STRESSES; TEMPERATURE RANGE 0273-0400 K; TRANSISTORS

Citation Formats

Jiang, R., E-mail: rong.jiang@vanderbilt.edu, Chen, J., Duan, G. X., Zhang, E. X., Schrimpf, R. D., Shen, X., Department of Physics and Materials Science, University of Memphis, Memphis, Tennesse 38152, Fleetwood, D. M., Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennesse 37235, Kaun, S. W., Kyle, E. C. H., Speck, J. S., Pantelides, S. T., and Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennesse 37235. Degradation and annealing effects caused by oxygen in AlGaN/GaN high electron mobility transistors. United States: N. p., 2016. Web. doi:10.1063/1.4958706.
Jiang, R., E-mail: rong.jiang@vanderbilt.edu, Chen, J., Duan, G. X., Zhang, E. X., Schrimpf, R. D., Shen, X., Department of Physics and Materials Science, University of Memphis, Memphis, Tennesse 38152, Fleetwood, D. M., Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennesse 37235, Kaun, S. W., Kyle, E. C. H., Speck, J. S., Pantelides, S. T., & Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennesse 37235. Degradation and annealing effects caused by oxygen in AlGaN/GaN high electron mobility transistors. United States. doi:10.1063/1.4958706.
Jiang, R., E-mail: rong.jiang@vanderbilt.edu, Chen, J., Duan, G. X., Zhang, E. X., Schrimpf, R. D., Shen, X., Department of Physics and Materials Science, University of Memphis, Memphis, Tennesse 38152, Fleetwood, D. M., Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennesse 37235, Kaun, S. W., Kyle, E. C. H., Speck, J. S., Pantelides, S. T., and Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennesse 37235. 2016. "Degradation and annealing effects caused by oxygen in AlGaN/GaN high electron mobility transistors". United States. doi:10.1063/1.4958706.
@article{osti_22590614,
title = {Degradation and annealing effects caused by oxygen in AlGaN/GaN high electron mobility transistors},
author = {Jiang, R., E-mail: rong.jiang@vanderbilt.edu and Chen, J. and Duan, G. X. and Zhang, E. X. and Schrimpf, R. D. and Shen, X. and Department of Physics and Materials Science, University of Memphis, Memphis, Tennesse 38152 and Fleetwood, D. M. and Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennesse 37235 and Kaun, S. W. and Kyle, E. C. H. and Speck, J. S. and Pantelides, S. T. and Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennesse 37235},
abstractNote = {Hot-carrier degradation and room-temperature annealing effects are investigated in unpassivated ammonia-rich AlGaN/GaN high electron mobility transistors. Devices exhibit a fast recovery when annealed after hot carrier stress with all pins grounded. The recovered peak transconductance can exceed the original value, an effect that is not observed in control passivated samples. Density functional theory calculations suggest that dehydrogenation of pre-existing O{sub N}-H defects in AlGaN plays a significant role in the observed hot carrier degradation, and the resulting bare O{sub N} can naturally account for the “super-recovery” in the peak transconductance.},
doi = {10.1063/1.4958706},
journal = {Applied Physics Letters},
number = 2,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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  • We investigate degradation mechanisms in AlGaN/GaN HEMTs which were repeatedly driven into the current-controlled off-state breakdown or subject to 60 s voltage- or current-controlled off state stresses. The current-controlled sweep in to the breakdown allows the sustainability of breakdown that can not be observed in the voltage controlled sweep. Only temporal changes were observed in the HEMT dc performance after repetitive sweeps, which were explained by charging/discharging of the HEMT surface at the gate-to-drain access region and in the GaN buffer below the gate. Similar changes were observed also if high-voltage stress has been applied on the drain; however, permanentmore » degradation appears after 60 s current-controlled breakdown stress. In this case, the drain leakage current, as well as the breakdown current, increases significantly. On the other hand, the breakdown voltage, as well as the gate characteristics, remains unaltered. We suggest that the avalanche-injection process is governing the off-state breakdown event with a dominant role of the potential barrier at the channel-buffer interface.« less