Hostname: page-component-84b7d79bbc-4hvwz Total loading time: 0 Render date: 2024-07-25T06:53:55.387Z Has data issue: false hasContentIssue false
  • English
  • Français

Analysis of InGaN-GaN quantum well chemistry and interfaces by transmission electron microscopy and X-ray scattering

Published online by Cambridge University Press:  01 February 2011

T. M. Smeeton ,
M. J. Kappers ,
J. S. Barnard  and
C. J. Humphreys
T. M. Smeeton
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, United Kingdom
M. J. Kappers
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, United Kingdom
J. S. Barnard
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, United Kingdom
C. J. Humphreys
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ, United Kingdom
Get access

Abstract

We have studied the distribution of indium in InxGa1-xN single quantum wells (SQWs) with compositions of In0.18Ga0.82N and In0.22Ga0.78N. Based on lattice parameter maps extracted from HRTEM lattice fringe images, we do not find evidence for strong nanometre-scale fluctuations in the composition of the wells (indium “clusters”). Z-contrast (high-angle annular dark field) scanning TEM (STEM) and X-ray reflectivity (XRR) results both show that the width of the interface at the top of the quantum well is slightly greater than that at the bottom, which is quite abrupt. The quantum wells exhibit bright photoluminescence so these results suggest that the conventional explanation for the high efficiency of light emission from InGaN LEDs may not apply in these structures.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 798: Symposium Y – GaN and Related Alloys , 2003 , Y5.36
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. Ho, I. and Stringfellow, G.B., Appl. Phys. Lett. 69, 2701 (1996)Google Scholar
2. Gerthsen, D., Hahn, E., Neubauer, B., Rosenauer, A., Schön, O., Heuken, M. and Rizzi, A., phys. stat. sol. (a) 177, 145 (2000)Google Scholar
3. Chichibu, S., Sota, T., Wada, K. and Nakamura, S., J. Vac. Sic. Technol. B 16, 2204 (1998)Google Scholar
4. Smeeton, T.M., Kappers, M.J., Barnard, J.S., Vickers, M.E. and Humphreys, C.J., phys. stat. sol. (b) 240, 297 (2003)Google Scholar
5. Smeeton, T.M., Kappers, M.J., Barnard, J.S., Vickers, M.E. and Humphreys, C.J., Appl. Phys. Lett., [DOI: 10.1063/1.1636534] in press (2003)Google Scholar
6. Parratt, L.G., Phys. Rev. 95, 359 (1954)Google Scholar
7. Névot, L. and Croce, P., Revue Phys. Appl. 15, 761 (1980)Google Scholar
8. Vurgaftman, I. and Meyer, J.R., J. Appl. Phys. 94, 3675 (2003)Google Scholar