Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-02T23:54:16.807Z Has data issue: false hasContentIssue false

Growth and Investigation of GaN/AlN Quantum Dots

Published online by Cambridge University Press:  17 March 2011

Hadis Morkoç
Affiliation:
Virginia Commonwealth University, Richmond, VA 23284, U.S.A.
Michael A. Reshchikov
Affiliation:
Virginia Commonwealth University, Richmond, VA 23284, U.S.A.
Keith M. Jones
Affiliation:
Virginia Commonwealth University, Richmond, VA 23284, U.S.A.
Feng Yun
Affiliation:
Virginia Commonwealth University, Richmond, VA 23284, U.S.A.
Paolo Visconti
Affiliation:
Virginia Commonwealth University, Richmond, VA 23284, U.S.A. Also with Istituto per lo Studio di Nuovi Materiali per l' Elettronica, CNR, 73100 Lecce, Italy
Marshall I. Nathan
Affiliation:
Virginia Commonwealth University, Richmond, VA 23284, U.S.A.
Richard J. Molnar
Affiliation:
Lincoln Laboratory, Lexington, MA 02320, U.S.A.
Get access

Abstract

We have fabricated GaN quantum dots (QDs) in AlN confined layer structures by molecular beam epitaxy. The size distribution and density of the QDs have been estimated from an atomic force microscopy study. Very high quantum efficiency of photoluminescence (PL) has been obtained in some samples with QDs. Compared to the GaN bulk samples, it increased by orders of magnitude. In some samples the quantum size effect dominated, resulting in the blue-shift of the QD related PL peak, whereas in the samples with larger dots a red-shift up to 0.8 eV has been observed, which is related to strong polarization effects. We have observed a blue-shift of the PL peak with excitation intensity in the samples with large dots due to screening effect. The temperature-induced quenching of PL occurs at higher temperatures compared to bulk GaN due to the confinement of nonequilibrium carriers in the QDs. An excited state has been observed in some samples.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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. Gérard, J. M., Cabrol, O., and Sermage, B., Appl. Phys. Lett.,68, 3123 (1996).Google Scholar
2. Tanaka, S., Iwai, S., and Aoyagi, Y., Appl. Phys. Lett., 69, 4096 (1996).Google Scholar
3. Widmann, F., Daudin, B., Feuillet, G., Samson, Y., Rouvière, J. L., and Pelekanos, N., J. Appl. Phys., 83, 7618 (1998).Google Scholar
4. Widmann, F., Simon, J., Daudin, B., Feuillet, G., Rouvière, J. L., Pelekanos, N. T., and Fishman, G., Phys. Rev. B, 58, R15989 (1998).Google Scholar
5. Damilano, B., Grandjean, N., Semond, F., Massies, J., and Leroux, M., Appl. Phys. Lett., 75, 962, (1999).Google Scholar
6. Ramvall, P., Riblet, P., Nomura, S., Aoyagi, Y., and Tanaka, S., J. Appl. Phys. 87, 3883 (2000).Google Scholar