Investigation of V-defects formation in InGaN/GaN multiple quantum well grown on sapphire
| Autor: | S. Y. Chow, A.M. Yong, Xinhai Zhang, Chew Beng Soh, Soo Jin Chua |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Diffraction
Materials science Photoluminescence business.industry digestive oral and skin physiology Metals and Alloys chemistry.chemical_element Heterojunction Surfaces and Interfaces Surfaces Coatings and Films Electronic Optical and Magnetic Materials Crystallography chemistry Transmission electron microscopy Materials Chemistry Sapphire Optoelectronics business Layer (electronics) Indium Quantum well |
| Zdroj: | Thin Solid Films. 515:4496-4500 |
| ISSN: | 0040-6090 |
| DOI: | 10.1016/j.tsf.2006.07.181 |
| Popis: | In the growth of InGaN multiple quantum well structure, V-pits has been observed to be initiated at the threading dislocations which propagate to the quantum well layers with high indium composition and substantially thick InGaN well. A set of samples with varying indium well thickness (3–7.6 nm) and composition (10–30%) are grown and characterized by photoluminescence (PL), X-ray diffraction, transmission electron microscopy and atomic force microscopy. The indium content and the layer thicknesses in InGaN/GaN quantum well are determined by high-resolution X-ray diffraction (XRD) and TEM imaging. With indium composition exceeding 10%, strain at the InGaN/GaN interface leads to the generation of V-pits at the interlayers of the MQW. Higher indium composition and increase in thickness of a period (InGaN well plus the GaN barrier) appear to enhance pits generation. With thicker InGaN well and reduction in thickness of GaN to InGaN (or the R ratio), pit density is substantially reduced, but it results in greater inhomogeneity in the distribution of indium in the InGaN well. This leads to a broadened PL emission and affect the PL emission intensity. |
| Databáze: | OpenAIRE |
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