Spatial clustering of defect luminescence centers in Si-doped low resistivity Al0.82Ga0.18N
Spatial clustering of defect luminescence centers in Si-doped low resistivity Al0.82Ga0.18N
复制标题
DOI：
10.1063/1.4928667
复制
发表时间：
2015-08-17
影响因子：
4
通讯作者：
Martin, Robert W.
中科院分区：
文献类型：
--
作者：
Kusch, Gunnar;Nouf-Allehiani, M.;Martin, Robert W.
一系列的Si掺杂的AlN丰富的AlGaN层具有低折射率的特征在于通过纳米成像技术的组合。利用扫描电子显微镜的能力，可靠地调查相同的样品面积与不同的技术，它是可能的，以确定掺杂浓度，缺陷分布和形态对这些层的发光性能的影响。阴极射线发光表明，主要的缺陷发光依赖于Si掺杂浓度。对于较低掺杂的样品，最强的峰集中在3.36 eV和3.39 eV之间，而对于最高掺杂的样品，另外的更强的峰出现在3 eV处。这些峰分别归属于（V-III-O-N）（2-）络合物和V-III（3-）空位。使用阴极射线发光，二次电子，电子沟道对比度，和原子力显微镜的多模成像表明，这些峰的发光强度是不均匀分布的，但显示出强烈的依赖于地形和螺旋位错的分布。(C)2015年作者。
A series of Si-doped AlN-rich AlGaN layers with low resistivities was characterized by a combination of nanoscale imaging techniques. Utilizing the capability of scanning electron microscopy to reliably investigate the same sample area with different techniques, it was possible to determine the effect of doping concentration, defect distribution, and morphology on the luminescence properties of these layers. Cathodoluminescence shows that the dominant defect luminescence depends on the Si-doping concentration. For lower doped samples, the most intense peak was centered between 3.36 eV and 3.39 eV, while an additional, stronger peak appears at 3 eV for the highest doped sample. These peaks were attributed to the (V-III-O-N)(2-) complex and the V-III(3-) vacancy, respectively. Multimode imaging using cathodoluminescence, secondary electrons, electron channeling contrast, and atomic force microscopy demonstrates that the luminescence intensity of these peaks is not homogeneously distributed but shows a strong dependence on the topography and on the distribution of screw dislocations. (C) 2015 Author(s).