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Absence of Lateral Composition Fluctuations in Aberration-corrected STEM Images of an InGaN Quantum Well at Low Dose

Published online by Cambridge University Press:  16 May 2012

Andrew B. Yankovich
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin - Madison, Madison, WI 53706 U.S.A.
A. V. Kvit
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin - Madison, Madison, WI 53706 U.S.A.
X. Li
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284 U.S.A.
F. Zhang
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284 U.S.A.
V. Avrutin
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284 U.S.A.
H.Y. Liu
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284 U.S.A.
N. Izyumskaya
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284 U.S.A.
Ü. Özgür
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284 U.S.A.
H. Morkoç
Affiliation:
Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, VA 23284 U.S.A.
P. M. Voyles
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin - Madison, Madison, WI 53706 U.S.A.
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Abstract

By using aberration corrected scanning transmission electron microscopy we have found no small scale lateral In composition fluctuations exist in the In0.15Ga0.85N active region of a light emitting diode. Images were acquired at 2% of the electron dose known to create electron beam damage, so the acquired images reflect the intrinsic structure of the InGaN active region. Position averaged convergent beam electron diffraction reveals the local sample thickness where images were acquired is 4.8 nm, eliminating the possibility that the absence of composition variation was observed due to projection through a thick sample. In addition, 2-3 atomic layer steps were observed in the top surface of In0.08Ga0.92N layers and the In0.15Ga0.85N active layers, providing a possible mechanism for lateral carrier confinement.

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Articles
Copyright
Copyright © Materials Research Society 2012

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References

REFERENCES

1 Nakamura, S., Senoh, M., -ichi Nagahama, S., and Iwasa, N., Applied Physics Letters 70, 868870 (1997).Google Scholar
2 Pearton, S.J., Ren, F., Zhang, A.P., and Lee, K.P., Materials Science and Engineering 30, 55212 (2000).Google Scholar
3 Xie, J., Özgür, U., Fu, Y., Ni, X., Morkoç, H., Inoki, C.K., Kuan, T.S., Foreman, J.V., and Everitt, H.O., Applied Physics Letters 90, 041107 (2007).Google Scholar
4 Narukawa, Y., Kawakami, Y., Funato, M., Fujita, S., Fujita, S., and Nakamura, S., Applied Physics Letters 70, 981 (1997).Google Scholar
5 Singh, R., Doppalapudi, D., Moustakas, T.D., and Romano, L.T., Applied Physics Letters 70, 1089 (1997).Google Scholar
6 El-Masry, N. a., Piner, E.L., Liu, S.X., and Bedair, S.M., Applied Physics Letters 72, 4042 (1998).Google Scholar
7 Cho, H.K., Lee, J.Y., Sharma, N., Humphreys, C.J., Yang, G.M., Kim, C.S., Song, J.H., and Yu, P.W., Applied Physics Letters 79, 2594 (2001).Google Scholar
8 -hsiu Ho, I. and Stringfellow, G.B., Applied Physics Letters 69, 2701 (1996).Google Scholar
9 Sharma, N., Thomas, P., Tricker, D., and Humphreys, C., Applied Physics Letters 77, 1274 (2000).Google Scholar
10 Bartel, T.P., Specht, P., Ho, J.C., and Kisielowski, C., Philosophical Magazine 87, 19831998 (2007).Google Scholar
11 Smeeton, T.M., Kappers, M.J., Barnard, J.S., Vickers, M.E., and Humphreys, C.J., Applied Physics Letters 83, 5419 (2003).Google Scholar
12 Oliver, R.A., Galtrey, M.J., and Humphreys, C.J., Materials Science and Technology 24, 675681 (2008).Google Scholar
13 Li, X., Zhang, F., Okur, S., Avrutin, V., Liu, S.J., Özgür, Ü., Morkoç, H., Hong, S.M., Yen, S.H., Hsu, T.S., and Matulionis, A., Physica Status Solidi (a) 208, 29072912 (2011).Google Scholar
14 Ni, X., Li, X., Lee, J., Liu, S., Avrutin, V., Özgür, U., Morkoç, H., Matulionis, A., Paskova, T., Mulholland, G., and Evans, K.R., Applied Physics Letters 97, 13 (2010).Google Scholar
15 Li, X., Liu, H.Y., Liu, S., Ni, X., Wu, M., Avrutin, V., Izyumskaya, N., Özgür, Ü., and Morkoç, H., Physica Status Solidi (a) 207, 19931996 (2010).Google Scholar
16 Liu, H.Y., Li, X., Liu, S., Ni, X., Wu, M., Avrutin, V., Izyumskaya, N., Özgür, Ü., Yankovich, a. B., Kvit, a. V., Voyles, P.M., and Morkoç, H., Physica Status Solidi (C) 8, 15481551 (2011).Google Scholar
17 Voyles, P.M., Grazul, J.L., and a Muller, D., Ultramicroscopy 96, 25173 (2003).Google Scholar
18 Hartel, P., Ultramicroscopy 63, 93114 (1996).Google Scholar
19 LeBeau, J.M., Findlay, S.D., Allen, L.J., and Stemmer, S., Ultramicroscopy 110, 11825 (2010).Google Scholar
20 Kirkland, E.J., Advanced Computing in Electron Microscopy, 1st Edition (Springer, 1998).Google Scholar
21 Xiong, X. and Moss, S.C., Journal of Applied Physics 82, 2308 (1997).Google Scholar