• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nanotechnology >The effect of local atomic structure on the optical properties of GeSi self-assembled islands buried in silicon matrix - art. no. 115711
【24h】

The effect of local atomic structure on the optical properties of GeSi self-assembled islands buried in silicon matrix - art. no. 115711

机译：局部原子结构对埋在硅基质中的GeSi自组装岛的光学性能的影响-艺术没有。 115711

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The local atomic structure of GeSi self-assembled islands buried in a silicon matrix strongly influences the optical properties of such systems. In the present paper this structure was determined by x-ray absorption fine-structure (XAFS) spectroscopy and high resolution transmission electron microscopy (HRTEM) and used to build a schematic description of the band structure model. Quantitative analysis of the extended XAFS (EXAFS) spectrum was performed for three coordination shells around the Ge absorbing atom with multiple scattering taken into account. It was proved that the coordination number of elements in an alloy resulting from EXAFS analysis for all three coordination spheres (i.e. 'mixing degree' parameters) cannot be taken as the concentration of alloy but can be used together with a proper model of the alloy unit cell to calculate a realistic concentration. The fraction of Ge calculated in this way is consistent with HRTEM results. The found model of the unit cell was used to generate a x-ray absorption near edge structure spectrum by ab initio calculations. This approach yielded a spectrum in good agreement with the experimental one. The information gained from XAFS and HRTEM was then used for calculation of the band structure diagram. Results of the calculation are discussed and compared with the experimental photoluminescence spectrum.
机译：埋在硅基质中的GeSi自组装岛的局部原子结构极大地影响了此类系统的光学性能。在本文中，该结构通过X射线吸收精细结构（XAFS）光谱和高分辨率透射电子显微镜（HRTEM）确定，并用于建立能带结构模型的示意图。对围绕Ge吸收原子的三个配位壳进行了扩展XAFS（EXAFS）光谱的定量分析，并考虑了多次散射。事实证明，通过EXAFS分析得出的所有三个配位球中合金元素的配位数（即“混合度”参数）都不能作为合金的浓度，而是可以与合金单元的适当模型一起使用计算实际浓度的单元格。用这种方法计算的Ge分数与HRTEM结果一致。通过从头算计算，将所发现的晶胞模型用于在边缘结构光谱附近生成X射线吸收。这种方法产生的光谱与实验光谱非常吻合。然后将从XAFS和HRTEM获得的信息用于计算能带结构图。讨论了计算结果，并将其与实验光致发光光谱进行了比较。

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号