Australian Centre for Advanced Photovoltaics, School of Photovoltaic and Renewable Energy Engineering, UNSW Australia , Sydney 2052, Australia.
Centre for Micro-Photonics, Swinburne University of Technology , Melbourne 3122, Australia.
ACS Appl Mater Interfaces. 2016 Nov 23;8(46):31887-31893. doi: 10.1021/acsami.6b11675. Epub 2016 Nov 9.
Using advanced two-photon excitation confocal microscopy, associated with time-resolved spectroscopy, we characterize InGaN/GaN multiple quantum wells on nanorod heterostructures and demonstrate the passivation effect of a KOH treatment. High-quality InGaN/GaN nanorods were fabricated using nanosphere lithography as a candidate material for light-emitting diode devices. The depth- and time-resolved characterization at the nanoscale provides detailed carrier dynamic analysis helpful for understanding the optical properties. The nanoscale spatially resolved images of InGaN quantum well and defects were acquired simultaneously. We demonstrate that nanorod etching improves light extraction efficiency, and a proper KOH treatment has been found to reduce the surface defects efficiently and enhance the luminescence. The optical characterization techniques provide depth-resolved and time-resolved carrier dynamics with nanoscale spatially resolved mapping, which is crucial for a comprehensive and thorough understanding of nanostructured materials and provides novel insight into the improvement of materials fabrication and applications.
利用先进的双光子激发共焦显微镜，结合时间分辨光谱学，我们对纳米棒异质结构上的 InGaN/GaN 多量子阱进行了表征，并证明了 KOH 处理的钝化效果。使用纳米球光刻作为发光二极管器件的候选材料，制备了高质量的 InGaN/GaN 纳米棒。纳米尺度的深度和时间分辨特性提供了有助于理解光学性质的详细载流子动力学分析。同时获得了 InGaN 量子阱和缺陷的纳米尺度空间分辨图像。我们证明了纳米棒刻蚀可以提高光提取效率，并且发现适当的 KOH 处理可以有效地减少表面缺陷并增强发光。光学特性分析技术提供了具有纳米尺度空间分辨映射的深度分辨和时间分辨载流子动力学，这对于全面深入地理解纳米结构材料至关重要，并为改进材料制造和应用提供了新的见解。
