Structural and Optical Emission Uniformity of m-Plane InGaN Single Quantum Wells in Core–Shell Nanorods

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• 作者：Emmanuel D. Le Boulbar ; Paul R. Edwards ; Shahrzad Hosseini Vajargah ; Ian Griffiths ; Ionut Gîrgel ; Pierre-Marie Coulon ; David Cherns ; Robert W. Martin ; Colin J. Humphreys ; Chris R. Bowen ; Duncan W. E. Allsopp ; Philip A. Shields
• 刊名：Crystal Growth & Design
• 出版年：2016
• 出版时间：April 6, 2016
• 年：2016
• 卷：16
• 期：4
• 页码：1907-1916
• 全文大小：771K
• ISSN：1528-7505

文摘

Controlling the long-range homogeneity of core–shell InGaN/GaN layers is essential for their use in light-emitting devices. This paper demonstrates variations in optical emission energy as low as ∼7 meV·μm^–1 along the m-plane facets from core–shell InGaN/GaN single quantum wells as measured through high-resolution cathodoluminescence hyperspectral imaging. The layers were grown by metal organic vapor phase epitaxy on etched GaN nanorod arrays with a pitch of 2 μm. High-resolution transmission electron microscopy and spatially resolved energy-dispersive X-ray spectroscopy measurements demonstrate a long-range InN-content and thickness homogeneity along the entire 1.2 μm length of the m-plane. Such homogeneous emission was found on the m-plane despite the observation of short-range compositional fluctuations in the InGaN single quantum well. The ability to achieve this uniform optical emission from InGaN/GaN core–shell layers is critical to enable them to compete with and replace conventional planar light-emitting devices.