Cathodoluminescence spectral mapping of III-nitride structures
Cathodoluminescence spectral mapping of III-nitride structures
复制标题
DOI：
10.1002/pssa.200304089
复制
发表时间：
2004-03-01
影响因子：
2
通讯作者：
Watson, IM
中科院分区：
文献类型：
--
作者：
Martin, RW;Edwards, PR;Watson, IM
阴极射线发光光谱映射的范围III-氮化物半导体结构的表征的应用程序进行了说明。详细介绍了仪器开发进行这样的测量使用电子探针微量分析仪。发光数据的空间分辨率接近100 nm。该技术是增强的能力，同时进行X射线显微分析和电子成像。结果是从外延横向过度生长的GaN和InGaN/GaN结构使用单层SiO2和多层SiO2/ZrO 2掩模。应变和三腔形成的影响得到解决。InGaN外延层的技术的应用显示了与铟含量的微观变化直接相关的发光光谱的峰值波长的空间依赖性的移位。发射在较低的能量和强度降低的区域被证明具有较高的InN含量，反映等效的宏观观测。最后，光谱映射技术被用来分析从微米级的选择性生长的III-N金字塔的发光，表明可能形成的量子点在尖锐的尖端。(C)2004 WILEY-VCH Verlag GmbH & Co. KGaA，魏因海姆。
The application of cathodoluminescence spectral mapping to the characterisation of a range III-nitride semiconductor structures is described. Details are presented of the instrumentation developed to carry out such measurements using an electron probe micro-analyser. The spatial resolution of the luminescence data is similar to100 nm. The technique is enhanced by the ability to simultaneously perform X-ray microanalysis and electron imaging. Results are presented from epitaxially laterally overgrown GaN and InGaN/GaN structures using both single-layer SiO2 and multilayer SiO2/ZrO2 masks. Effects of strain and triierocavity formation are resolved. Application of the technique to InGaN epilayers shows spatially-dependent shifts in the peak wavelength of the luminescence spectrum which correlate directly with microscopic variations in the indium content. Regions emitting at lower energy and with decreased intensity are shown to have higher InN contents, mirroring equivalent macroscopic observations. Finally the spectral mapping technique is used to analyse the luminescence from micron-scale selectively grown III-N pyramids, indicating possible formation of quantum dots at the sharp tips. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.