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Impact of Small Miscuts of (0001) Sapphire on the Growth of AlxGa1-xN/AlN

Published online by Cambridge University Press:  01 February 2011

Zheng Gong ,
Wenhong Sun ,
Jianping Zhang ,
Mikhail E. Gaevski ,
Hongmei Wang ,
Jinwei Yang  and
M. Asif Khan
Zheng Gong
Affiliation:
Department of Electrical Engineering, University of South Carolina, 301 South Main Street, Columbia, SC 29208, USA
Wenhong Sun
Affiliation:
Department of Electrical Engineering, University of South Carolina, 301 South Main Street, Columbia, SC 29208, USA
Jianping Zhang
Affiliation:
Sensor Electronic Technology Inc., Columbia, SC 29209, USA
Mikhail E. Gaevski
Affiliation:
Department of Electrical Engineering, University of South Carolina, 301 South Main Street, Columbia, SC 29208, USA
Hongmei Wang
Affiliation:
Department of Electrical Engineering, University of South Carolina, 301 South Main Street, Columbia, SC 29208, USA
Jinwei Yang
Affiliation:
Department of Electrical Engineering, University of South Carolina, 301 South Main Street, Columbia, SC 29208, USA
M. Asif Khan
Affiliation:
Department of Electrical Engineering, University of South Carolina, 301 South Main Street, Columbia, SC 29208, USA
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Abstract

In this paper, using chemical etching, atomic force microscope (AFM) and High- resolution X-ray diffraction (HRXRD), we report a study of the effect of various small miscuts of (0001) sapphire substrate (<1°) and the way to further improve the material quality. A set of AlN epilayers and AlN/AlxGa1-xN Superlattices (SLs) were grown by Migration-enhanced Metalorganic Chemical Vapor Deposition (MEMOCVD) on vicinal (0001) sapphire substrates. The threading dislocation density was found to be very sensitive to the miscut angles. The etch pit density reduced to 7×106 cm-2 for normal-oriented (0°-off) from the starting value of 7×107 cm-2 for 0.5°-off. We found the surface morphologies can be easily controlled by the different substrate miscut angles. The 1-2 Monolayers (MLs) step flow morphology for normal- oriented substrate changed to step bunches of 10 MLs height for 0.5°-off substrate. Correspondingly, AFM Root Mean Square (RMS) increased from 1.52 to 9.15 Å with a 5um×5um scan. This finding may help enhance the quality of full structure UVLED material and eventually improve the lifetime of UVLEDs.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 864: Symposium E – Semiconductor Defect Engineering-Materials, Synthesis Structures and Devices , 2005 , E4.34
Copyright
Copyright © Materials Research Society 2005

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References

[1] Fischer, A. J., Allerman, A. A., Crawford, M. H., Bogart, K. H. A., Lee, S. R., Kaplar, R. J., Chow, W. W., Kurtz, S. R., Fullmer, K. W., Figiel, J. J., Appl. Phys. Lett. 84 3394 (2004).Google Scholar
[2] Sun, W. H., Zhang, J. P., Adivarahan, V., Chitnis, A., Shatalov, M., Wu, S., Mandavilli, V., Yang, J. W., Khan, M. A., Applied Physics Letters 85, 531(2004).Google Scholar
[3] Advarahan, V., Chitnis, A., Zhang, J. P., Shatalov, M., Yang, J. W., Simin, G., Khan, M. Asif, Shur, M., and Gaska, R., Appl. Phys. Lett. 79, 4240(2001)Google Scholar
[4] Shen, Xu-Qiang, Shimizu, Mitsuaki and Okumura, Hjime, Jpn. J. Appl. Phys. Vol. 42 (2003) pp. L1293– L1295.Google Scholar
[5] Zhang, Jp, Khan, Ma, Sun, Wh, Wang, Hm, Chen, Cq, Fareed, Q, Kuokstis, E, and Yang, Jw, Applied Physics Letters, 81(23):4392–4394(2002)Google Scholar
[6] Sun, W. H., Yang, J. W., Zhang, J. P., Gaevski, M. E., Chen, C. Q., Li, J. W., Gong, Z., Su, M., and Khan, M. Asif, phys. stat. sol. (c), 1–4 (2005)Google Scholar
[7] Gong, Zheng, Sun, Wenhong, Wang, Hongmei, , Mikhail, Gaevski, E., Yang, Jinwei, and Khan, M. Asif, to be publishedGoogle Scholar