Hostname: page-component-76fb5796d-vfjqv Total loading time: 0 Render date: 2024-04-26T08:09:16.683Z Has data issue: false hasContentIssue false
  • English
  • Français

TEM investigation of defect reduction and etch pit formation in GaN

Published online by Cambridge University Press:  01 February 2011

Angelika Vennemann ,
Jens Dennemarck ,
Roland Kröger ,
Tim Böttcher ,
Detlef Hommel  and
Peter Ryder
Angelika Vennemann
Affiliation:
Institute of Solid State Physics, University of Bremen, P. O. Box 330440, 28334 Bremen, Germany
Jens Dennemarck
Affiliation:
Institute of Solid State Physics, University of Bremen, P. O. Box 330440, 28334 Bremen, Germany
Roland Kröger
Affiliation:
Institute of Solid State Physics, University of Bremen, P. O. Box 330440, 28334 Bremen, Germany
Tim Böttcher
Affiliation:
Institute of Solid State Physics, University of Bremen, P. O. Box 330440, 28334 Bremen, Germany
Detlef Hommel
Affiliation:
Institute of Solid State Physics, University of Bremen, P. O. Box 330440, 28334 Bremen, Germany
Peter Ryder
Affiliation:
Institute of Solid State Physics, University of Bremen, P. O. Box 330440, 28334 Bremen, Germany
Get access

Abstract

GaN samples of this study were chemically wet etched to gain easier access to the dislocation sturcture. The scanning electron microscopy and transmission electron microscopy investigations revealed four different types of etch pits. After brief etching, several dislocations with screw component showed large etch pits, which may be correlated with the core of the screw dislocation. By means of SiNx micromasking the dislocation density could be reduced by more than one order of magnitude. The reduction of threading dislocations in the SiNx region in GaN grown on 〈0001〉 sapphire is due to bending of the threading dislocations into the {0001} plane, such that they form dislocation loops if they meet dislocations with opposite Burgers vectors. Accordingly, the achievable reduction of the dislocation density is limited by the probability that these dislocations interact. Edge dislocations bend more easily on account of their low line tension. This results in a preferential bending and reduction of dislocations with edge character.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 798: Symposium Y – GaN and Related Alloys , 2003 , Y5.22
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Speck, J. S., and Rosner, S. J., Physica B 273–274, 24 (1999).Google Scholar
2. Tanaka, S., Iwai, S., and Aoyagi, Y., J. Cryst. Growth 170, 329 (1997).Google Scholar
3. Tanaka, S., Iwai, S., and Aoyagi, Y., Appl. Phys. Lett. 69, 4096 (1996).Google Scholar
4. Vennéguès, P., Beaumont, B., Haffouz, S., Vaille, M., and Gibart, P., J. Cryst. Growth 187, 167 (1998).Google Scholar
5. Tanaka, S., Takeuchi, M., and Aoyagi, Y., Jpn. J. Appl. Phys. 39, L831 (2000).Google Scholar
6. Haffouz, S., Kirilyuk, V., Hageman, P. R., Macht, L., Weyher, J. L., and Larsen, P. K., Appl. Phys. Lett. 79, 2390 (2001).Google Scholar
7. Contreras, O., Ponce, F. A., Christen, J., Dadgar, A., and Krost, A., Appl. Phys. Lett. 81, 4712 (2002).Google Scholar
8. Dadgar, A., Poschenrieder, M., Bläsing, J., Contreras, O., Bertram, F., Riemann, T., Reiher, A., Kunze, M., Daumiller, I., Krtschil, A., Diez, A., Kaluza, A., Modlich, A., Kamp, M., Christen, J., Ponce, F. A., Kohn, E., and Krost, A., J. Cryst. Growth 248, 556 (2003).Google Scholar
9. Engl, K., Beer, M., Zweck, J., Miller, S., Bader, S., Lugauer, H.-J., Brüderl, G., Lell, A., and Härle, V., Microsc. Microanal. 9, 70 (2003).Google Scholar
10. Hong, S. K., Kim, B. J., Park, H. S., Park, Y., Yoon, S. Y., and Kim, T. I., J. Cryst. Growth 191, 275 (1998).Google Scholar
11. Hong, S. K., Yao, T., Kim, B. J., Yoon, S. Y., and Kim, T. I., Appl. Phys. Lett. 77, 82 (2000).Google Scholar
12. Weyher, J. L., Macht, L., Kamler, G., Borysiuk, J., and Grzegory, I., phys. stat. sol. (c) 0, 821 (2003).Google Scholar
13. Böttcher, T., Dennemarck, J., Kröger, R., Figge, S., and Hommel, D., phys. stat. sol (c) 0, 2039 (2003).Google Scholar
14. Hirth, J. P., and Lothe, J., Theory of Dislocations 2nd ed. (John Wiley & Sons, Inc., New York, 1982).Google Scholar
15. Kisielowski, C., Krüger, J., Ruvimov, S., Suski, T., Ager, J. W. III, Jones, E., Liliental-Weber, Z., Rubin, M., Weber, E. R., Bremser, M. D., and Davis, R. F., Phys. Rev. B 54, 17745 (1996).Google Scholar
16. Wu, X. H., Brown, L. M., Kapolnek, D., Keller, S., Keller, B., DenBaars, S. P., and Speck, J. S., J. Appl. Phys. 80, 3228 (1996).Google Scholar
17. Ning, X. J., Chien, F. R., Pirouz, P., Yang, J. W., and Asif Khan, M., J. Mater. Res. 11, 580 (1996).Google Scholar