Abstract
This review concentrates on the microstructure of InxGa1−xN layers and quantum wells (QWs) in relation to their optical properties. The microstructure of InxGa1−xN, with a constant In(x) concentration, shifts with layer thickness. Only layers below 100 nm for x = 0.1 are nearly defect-free. A photoluminescence peak is observed at 405 nm, in line with ∼10% In, suggesting band-edge luminescence. Layers with greater thickness and In content present a corrugated surface with numerous structural defects, including V-defects, causing redshifts and multi-peaks in photoluminescence up to 490 nm. These defects, resembling those in GaN, lead to a corrugated sample surface. Atomic force microscopy shows a 3.7-fold larger corrugation in samples with 20 QWs compared to those with 5 QWs measured on 2 × 2 μm2 areas. Like in GaN, dual growth on different crystallographic planes results in varied QW thicknesses, influencing optical traits of devices made from InxGa1−xN layers. The purpose of this review and the chosen subject is to highlight the significant contribution of Wladek Walukiewicz and his group to the current research on the properties of InxGa1−xN, which are crucial alloys in the field of optoelectronics.
| Original language | English (US) |
|---|---|
| Article number | 095703 |
| Journal | Journal of Applied Physics |
| Volume | 135 |
| Issue number | 9 |
| DOIs | |
| State | Published - Mar 7 2024 |
Funding
This paper was devoted to the memory of Wladek Walukiewicz on the first anniversary of his death. The subject of this paper was chosen to remember our work in one group and Wladek’s contribution to determine a low bandgap in InN and show the importance of this work for today’s research. The experimental work was supported by the Director, Office of Science, Office of Basic Energy Sciences, Division of Materials Science and Engineering, of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098. The authors wish to thank all colleagues who contributed to the original publications based on which this manuscript could be written: Dr. K. M. Yu the closest co-worker of Dr. Walukiewicz, Dr. J. Wu, J. W. Ager, all crystal growers Dr. S. M. Bedair, Dr. S. Nakamura, Dr. W. J. Schaff, Dr. M. C. Johnson, and Dr. E. D. Bourret-Courchesne as well as all colleagues who used a variety of experimental methods working together on the same samples to understand the InGaN microstructure and optical properties of these alloys: Dr. D. F. Ogletree, Dr. J. Z. Domagala, Dr. J. Bak-Misiuk, Dr. M. Hawkridge, Dr. J. Jasinski, Dr. M. Benamara, and Dr. C. Kisielowski.
ASJC Scopus subject areas
- General Physics and Astronomy