Low-pressure metal-organic chemical vapor deposition (MOCVD) has been used to deposit unnucleated and self-nucleated GaN thin films on (00.1) sapphire substrates. For the self-nucleated films, initial layers were grown at 540°C using trimethylgallium and ammonia as elemental sources and either nitrogen or hydrogen as the carrier gas. Using these same gas phase conditions, overlayers on native (00.1) sapphire substrates or the GaN-nucleated (00.1) sapphire substrates were deposited at 1025°C. The surface morphology and mosaic dispersion of these unnucleated and self-nucleated GaN thin films have been surveyed by a combination of real space images from atomic force microscopy and reciprocal space intensity data from X-ray scattering measurements. As expected, the unnucleated GaN films show a large-grained hexagonal relief, typical of three-dimensional island growth. However, the self-nucleated films are shown to be dense mosaics of highly oriented islands, emblematic of a more two-dimensional growth.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
G. Strang & G. Fix, An Analysis of the Finite Element Method, Prentice Hall, Englewood Cliffs, NJ (1973).
H. Amano, N. Sawaki, I. Akasaki, and Y. Toyoda, Appl. Phys. Lett. 48, 353 (1986).
D. K. Wickenden, T. J. Kistenmacher, W. A. Bryden, J. S. Morgan, and A. Estes Wickenden, Mat. Res. Soc. Symp. Proc. 221, 167 (1991).
S. Nakamura, Jpn. J. Appl. Phys. 30, L1705 (1991).
M. A. Khan, J. N. Kuznia, J. M. Van Hove, D. T. Olson, S. Krishnankutty, and R. M. Kolbas, Appl. Phys Lett. 58, 526 (1991).
B. Goldenberg, J. D. Zook, and R. J. Ulmer, Appl. Phys. Lett. 62, 381 (1993).
W. E. Piano, J. S. Major Jr., D. F. Welch, and J. Speirs, Electron. Lett. 30, 2079 (1994).
K. Doverspike, L. B. Rowland, D. K. Gaskill, and J. A. Freitas, Jr., J. Electron. Mat. 24, 269 (1995).
H. P. Maruska and J. J. Tietjen, Appl. Phys. Lett. 15, 327 (1969).
M. Ilegems, J. Crystal Growth 13/14, 360 (1972).
D. K. Wickenden, K. R. Faulkner, R. W. Brander, and B. J. Isherwood, J. Crystal Growth 9, 158 (1971).
D. K. Wickenden, C. B. Bargeron, W. A. Bryden, J. Miragliotta, and T. J. Kistenmacher, Appl. Phys. Lett. 65, 2024 (1994).
See, for example, D. Kapolnek, X. H. Xu, B. Heying, S. Keller, B. P. Keller, U. K. Mishra, S. P. DenBaars, and J. S. Speck, Appl. Phys. Lett. 67, 1541 (1995).
About this article
Cite this article
Kistenmacher, T., Wickenden, D., Hawley, M. et al. Effect of Carrier Gas on the Surface Morphology and Mosaic Dispersion for GaN Films by Low-Pressure MOCVD. MRS Online Proceedings Library 395, 261–266 (1995). https://doi.org/10.1557/PROC-395-261