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Direct AFM Observation of Strain Effects on MOCVD-Grown GaN Epilayer Surface Morphology

Published online by Cambridge University Press:  01 February 2011

D.I. Florescu ,
D.S. Lee ,
J.C. Ramer ,
V.N. Merai ,
A. Parekh ,
D. Lu ,
E.A. Armour  and
W.E. Quinn
D.I. Florescu
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
D.S. Lee
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
J.C. Ramer
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
V.N. Merai
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
A. Parekh
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
D. Lu
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
E.A. Armour
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
W.E. Quinn
Affiliation:
Veeco Compound Semiconductor, Advanced Technology Group, 394 Elizabeth Avenue, Somerset, NJ 08873, USA
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Abstract

In this study, we investigate the dependence of GaN surface morphology on the absolute strain values for thin (<10 μm) epitaxial films grown by MOCVD on c-plane sapphire substrates of various miscut angles towards the m-plane. Results indicate an excellent correlation between the surface roughness observed employing an AFM tool and epilayer strain values. An overall increase of surface roughness (decrease of atomic terrace width) is found with decreasing compressive strain (epilayer vs. bulk value). In addition, sapphire substrates with increasing miscut angle (0.30 deg) appear to relax the inherent, built-in strain differently in the vertical (growth) direction when compared to just (0.00 deg) substrates. Strain relaxation by typical V-shaped, hexagonal pits is directly imaged through the comparison of surface features inside and outside of pits in the thin GaN epilayer films.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 831: Symposium E – GaN, AlN, InN, and Their Alloys , 2004 , E11.6
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

[1] Xie, Y.H., Gilmer, G.H., Roland, C., Silverman, P.J., Buratto, S.K., Cheng, J. Y., Fitzgerald, E.A., Kortan, A.R., Schuppler, S., Marcus, M.A., and Citrin, P.H., Phys. Rev. Lett. 73, 3006 (1994).Google Scholar
[2] Fitzgerald, E.A., Samavedam, S.B., Xie, Y.H., and Giovane, L.M., J. Vac. Sci. Technol. A 15(3), 1048 (1997).Google Scholar
[3] Pearton, S. J., Zolper, J. C., Shul, R. J., and Ren, F., J. Appl. Phys. 86, 1 (1999).Google Scholar
[4] Matsuoka, T., Okamoto, H., Nakao, M., Harima, H., and Kurimoto, E., Appl. Phys. Lett. 81, 1246 (2002).Google Scholar
[5] Florescu, D.I., Ramer, J.C., Lee, D.S., Merai, V.N., Parekh, A., Lu, D., and Armour, E.A., Veeco Apps. Note 1/04, 1 (2004).Google Scholar
[6] Florescu, D.I., Ramer, J.C., Ting, S.M., Merai, V.N., Parekh, A., Lu, D., Lee, D.S., and Armour, E.A., Veeco Apps. Note 2/04, 1 (2004).Google Scholar
[7] Ramer, J.C., Florescu, D.I., Lee, D.S., Liu, L., and Armour, E.A. in Proceedings of the 204th ECS Meeting, Orlando, FL October 12–16 (2003).Google Scholar
[8] Florescu, D.I., Ting, S.M., Ramer, J.C., Lee, D.S., Merai, V.N., Parekh, A., Lu, D., Armour, E.A., and Chernyak, L., Appl. Phys. Lett. 83, 33 (2003).Google Scholar
[9] Lu, D., Florescu, D.I., Lee, D.S., Merai, V., Parekh, R., Ramer, J.C., Guo, S.P., and Armour, E.A., Phys. Stat. Sol. (a) 195, 3 (2003).Google Scholar