Abstract
We investigated the effects of oxygen annealing on electrical characteristics of AlGaN/GaN heterostructures grown on Si by metalorganic chemical vapor deposition. It was shown that such treatment suppresses parasitic tunneling leakage current due to surface states or dislocations, decreases the threshold voltage corresponding to depletion of the two-dimensional electron gas at the AlGaN interface, and increases the effective interdevice isolation resistance. The suppression of the leakage current is explained by oxygen passivation of the empty states at the surface of the AlGaN barrier. Oxygen diffusion along dislocations and passivation of dislocation related states also could play a role. The decreased threshold voltage is attributed to the increased concentration of possibly oxygen related deep traps near the AlGaN/GaN interface. The increase in the GaN buffer resistivity after annealing is ascribed to the annihilation of the 0.38 eV deep electron traps believed to be introduced at the surface of GaN during mesa formation by dry etching.
| Original language | English |
|---|---|
| Pages (from-to) | 17-23 |
| Number of pages | 7 |
| Journal | Journal of Alloys and Compounds |
| Volume | 575 |
| DOIs | |
| Publication status | Published - 2013 Jan 1 |
| Externally published | Yes |
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Keywords
- AlGaN/GaN HEMT
- Deep traps
- Leakage current
- Oxygen annealing
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry
Cite this
Effects of annealing in oxygen on electrical properties of AlGaN/GaN heterostructures grown on Si. / Polyakov, A. Y.; Smirnov, N. B.; Ha, Min Woo; Hahn, Cheol Koo; Kozhukhova, E. A.; Govorkov, A. V.; Ryzhuk, R. V.; Kargin, N. I.; Cho, Han Su; Lee, In-Hwan.
In: Journal of Alloys and Compounds, Vol. 575, 01.01.2013, p. 17-23.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effects of annealing in oxygen on electrical properties of AlGaN/GaN heterostructures grown on Si
AU - Polyakov, A. Y.
AU - Smirnov, N. B.
AU - Ha, Min Woo
AU - Hahn, Cheol Koo
AU - Kozhukhova, E. A.
AU - Govorkov, A. V.
AU - Ryzhuk, R. V.
AU - Kargin, N. I.
AU - Cho, Han Su
AU - Lee, In-Hwan
PY - 2013/1/1
Y1 - 2013/1/1
N2 - We investigated the effects of oxygen annealing on electrical characteristics of AlGaN/GaN heterostructures grown on Si by metalorganic chemical vapor deposition. It was shown that such treatment suppresses parasitic tunneling leakage current due to surface states or dislocations, decreases the threshold voltage corresponding to depletion of the two-dimensional electron gas at the AlGaN interface, and increases the effective interdevice isolation resistance. The suppression of the leakage current is explained by oxygen passivation of the empty states at the surface of the AlGaN barrier. Oxygen diffusion along dislocations and passivation of dislocation related states also could play a role. The decreased threshold voltage is attributed to the increased concentration of possibly oxygen related deep traps near the AlGaN/GaN interface. The increase in the GaN buffer resistivity after annealing is ascribed to the annihilation of the 0.38 eV deep electron traps believed to be introduced at the surface of GaN during mesa formation by dry etching.
AB - We investigated the effects of oxygen annealing on electrical characteristics of AlGaN/GaN heterostructures grown on Si by metalorganic chemical vapor deposition. It was shown that such treatment suppresses parasitic tunneling leakage current due to surface states or dislocations, decreases the threshold voltage corresponding to depletion of the two-dimensional electron gas at the AlGaN interface, and increases the effective interdevice isolation resistance. The suppression of the leakage current is explained by oxygen passivation of the empty states at the surface of the AlGaN barrier. Oxygen diffusion along dislocations and passivation of dislocation related states also could play a role. The decreased threshold voltage is attributed to the increased concentration of possibly oxygen related deep traps near the AlGaN/GaN interface. The increase in the GaN buffer resistivity after annealing is ascribed to the annihilation of the 0.38 eV deep electron traps believed to be introduced at the surface of GaN during mesa formation by dry etching.
KW - AlGaN/GaN HEMT
KW - Deep traps
KW - Leakage current
KW - Oxygen annealing
UR - http://www.scopus.com/inward/record.url?scp=84877090601&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84877090601&partnerID=8YFLogxK
U2 - 10.1016/j.jallcom.2013.04.020
DO - 10.1016/j.jallcom.2013.04.020
M3 - Article
VL - 575
SP - 17
EP - 23
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
SN - 0925-8388
ER -