拼接双范围EELS光谱:识别和纠正文物
Alan J Craven1, Bianca Sala2, Donald A MacLaren1
1SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK.
Ultramicroscopy
|April 8, 2025
概括
电子能量损失光谱 (EELS) 拼接中的工件使用新方法进行了纠正. 这提高了EELS数据的定量分析,即使在系统变化之后.
科学领域:
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
- 电子显微镜电子显微镜
背景情况:
- 电子能量损失光谱 (EELS) 需要将低和核心损失光谱拼接起来进行全范围分析.
- 在EELS中的大动态范围导致在拼接点的强度很小,放大了文物效应.
研究的目的:
- 在EELS数据拼接中调查和纠正文物.
- 提高EELS分析的定量准确性,特别是在Gatan GIF量子系统中.
主要方法:
- 确定了三个主要的文物来源:光谱仪的光学偏差,探测器漫游散射和探测器象限响应差异.
- 开发了测量,量化和纠正这些特定文物的方法.
- 通过比较校正前后的缩放因子来验证校正.
主要成果:
- 文物导致缩放因子偏离~15%并取决于样品厚度.
- 在校正后,缩放因子的差异减少到<0.5%.
- 证明了在不同时间点和系统配置中对EELS数据进行定量比较的能力.
结论:
- 开发的方法有效地纠正了EELS数据拼接中的文物.
- 通过这些纠正,可以准确地对EELS数据进行定量比较.
- 这些原则适用于各种光谱仪,包括具有直接电子探测器的光谱仪.
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