Modified qHAADF method for atomic column-by-column compositional quantification of semiconductor heterostructures
Modified qHAADF method for atomic column-by-column compositional quantification of semiconductor heterostructures
复制标题
DOI：
10.1007/s10853-018-3073-y
复制
发表时间：
2018-11
影响因子：
4.5
通讯作者：
A. Khan;M. Herrera;J. Pizarro;P. Galindo;P. Carrington;H. Fujita;A. Krier;S. Molina
中科院分区：
文献类型：
--
作者：
A. Khan;M. Herrera;J. Pizarro;P. Galindo;P. Carrington;H. Fujita;A. Krier;S. Molina
qHAADF方法允许通过比较感兴趣区域与已知组成的材料区域之间的HAADF-STEM强度来以原子柱分辨率定量半导体材料中的组成。然而，这种qHAADF方法的应用需要两个区域是可区分的，并且在非常接近的情况下包括在同一显微照片中。这限制了该方法在满足该要求的某些材料和放大率中的应用。在这项工作中，我们将qHAADF方法扩展到参考区域在单独的显微照片中成像的分析。用半导体异质结构InSb/InAs的HAADF-STEM模拟图像与原始的qHAADF方法进行比较，证明了这种改进方法的有效性。此外，该方法被成功地应用到实验图像的一个简单的InSb/InAs接口和一个复杂的InSb/GaSb异质结构，证明了修改后的方法比原来的方法的意义。
The qHAADF method allows the quantification of the composition at atomic column resolution in semiconductor materials by comparing the HAADF-STEM intensities between a region of interest to a region of the material of known composition. However, the application of this qHAADF approach requires both regions to be differentiable and included in the same micrograph at close proximity. This limits the application of this approach to certain materials and magnifications where this requirement is fulfilled. In this work, we extend the qHAADF method to analyses where the reference region is imaged in a separate micrograph. The validity of this modified method is proved by comparison to the original qHAADF approach using HAADF-STEM simulated images of the semiconductor heterostructure InSb/InAs. Additionally, the methods are applied successfully to experimental images both of a simple InSb/InAs interface and of a complex InSb/GaSb heterostructure, justifying the significance of the modified method over the original method.