Cathodoluminescence study of single zinc oxide nanopillars with high spatial and spectral resolution
Cathodoluminescence study of single zinc oxide nanopillars with high spatial and spectral resolution
复制标题
具有高空间和光谱分辨率的单个氧化锌纳米柱的阴极发光研究
DOI：
10.1063/1.2735411
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发表时间：
2007
影响因子：
3.2
通讯作者：
R. Sauer
中科院分区：
文献类型：
--
作者：
M. Schirra;A. Reiser;G. Prinz;A. Ladenburger;K. Thonke;R. Sauer
通过扫描电子显微镜中的纳米级空间分辨阴极荧光技术，对在a面蓝宝石上通过气 - 液 - 固工艺生长的单个氧化锌（ZnO）纳米柱进行了研究。通过沿单个纳米柱以及横跨下方的浸润层激发荧光来记录光谱。从被激发的纳米柱点发出的荧光呈现出尖锐的束缚激子线和本征自由激子复合，而浸润层仅显示出非常微弱的荧光。沿着纳米柱，几乎没有观察到谱线的移动。这被解释为纳米柱无应变生长的证据。在纳米柱的底部区域发现了来自衬底材料的铝掺入。有迹象表明由于源材料引入的无意掺杂，沿着纳米柱有镓的掺入。将点分辨结果与在同一样品区域进行的大面积激发的积分光致发光测量结果进行了比较。
Single zinc oxide (ZnO) nanopillars grown by the vapor-liquid-solid process on a-plane sapphire are investigated by spatially resolved cathodoluminescence on the nanometer scale in a scanning electron microscope. Spectra were recorded by exciting luminescence along single pillars and across the underlying wetting layer. Luminescence from the excited pillar spots exhibited sharp bound exciton lines and intrinsic free-exciton recombination, whereas the wetting layer showed only very weak luminescence. Along the pillars, virtually no shift of the lines was observed. This is interpreted as evidence for strain-free growth of the pillars. In the bottom region of the pillars aluminum incorporation from the substrate material was found. There are indications for an incorporation of gallium along the pillars due to unintentional doping introduced by the source material. The spot-resolved results are compared to integral photoluminescence measurements with large-area excitation carried out on the same sample region.