We investigate AlGaAs/GaAs superlattices as well as InGaAs/GaAs quantum wells and epitaxial quantum dots (QDs) where during the molecular beam epitaxy of InGaAs QDs the aluminium flux cell was opened briefly to incorporate fractional monolayers of Al into the InGaAs. We show that x-ray mapping with a large collection angle is capable of detecting 0.3–0.4 fractional Al monolayers with a resolution of just under 1 nm.

中文翻译：

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InGaAs量子点的扫描透射电子显微镜中的X射线映射以及嵌入的分数单层铝

我们研究了AlGaAs / GaAs超晶格以及InGaAs / GaAs量子阱和外延量子点（QDs），其中在InGaAs QD的分子束外延期间，铝通量池被短暂打开，以将Al的分数单层结合到InGaAs中。我们显示，具有大收集角的X射线映射能够检测0.3–0.4的分数Al单层，分辨率不到1 nm。