论文标题
通过扫描隧穿发光显微镜，探测Ingan/GAN量子井中的局部发射特性
Probing local emission properties in InGaN/GaN quantum wells by scanning tunneling luminescence microscopy
论文作者
论文摘要
扫描隧道电致发光显微镜在3 nm厚的Ingan/gan量子上很好地进行，X = 0.23，以使主要的光发射发生在绿色中。该技术用于以〜10 nm的比例绘制局部重组特性，并将其与扫描隧道显微镜成像的表面形貌相关联。探测了一个500 nm x 500 nm大的区域，探测了150 nm的150 nm和2.5 nm深的六边形缺陷，揭示了在接近缺陷边缘的较高能量下的发射，这一特征在样品的宏观发光光谱中不可见。通过局部隧道电致发光光谱的拟合，获得了有关不同光谱贡献的强度，能量，宽度和声子复制强度的波动的定量信息，从而揭示了有关量子井中载体定位的信息。该过程还表明，量子孔的探测部分上的载体扩散长度约为40 nm。
Scanning tunneling electroluminescence microscopy is performed on a 3-nm-thick InGaN/GaN quantum well with x = 0.23 such that the main light emission occurs in the green. The technique is used to map the local recombination properties at a scale of ~10 nm and to correlate them with the surface topography imaged by scanning tunneling microscopy. A 500 nm x 500 nm area around a 150-nm large and 2.5-nm deep hexagonal defect is probed, revealing emission at higher energies close to the defect edges, a feature which is not visible in the macro-photoluminescence spectrum of the sample. Via a fitting of the local tunneling electroluminescence spectra, quantitative information on the fluctuations of the intensity, energy, width and phonon replica intensity of the different spectral contributions are obtained, revealing information about carrier localization in the quantum well. This procedure also indicates that carrier diffusion length on the probed part of the quantum well is approximately 40 nm.
