在液相传输电子显微镜中氧化化膜的电子束氧化
Sofie Tidemand-Lichtenberg1, Shima Kadkhodazadeh1, Kristian Speranza Mølhave1
1National Centre of Nano Fabrication and Characterisation, DTU Nanolab, Technical University of Denmark, Kongens Lyngby, Denmark. krmo@dtu.dk.
Nanoscale
|July 14, 2025
概括
电子束辐射在液相传导电子显微镜中浸入水中时,将化膜转化为氧化. 膜中的这种光束诱导的化学变化可能会影响液体样本分析.
科学领域:
- 材料科学 材料科学 材料科学
- 电子显微镜电子显微镜
- 表面化学 表面化学
背景情况:
- 液相传导电子显微镜 (LPTEM) 研究往往忽视了电子束对封装材料的影响.
- 化 (SiNx) 薄膜通常用于LPTEM中的液体封装材料.
研究的目的:
- 在典型的LPTEM条件下 (浸水和电子束暴露) 调查SiNx薄膜中的化学变化.
- 了解电子束诱导的SiNx膜变化对LPTEM实验的影响.
主要方法:
- 扫描传输电子显微镜 (STEM) 用于成像.
- 电子能量损失光谱 (EELS) 用于化学和结构分析.
- 在电子束辐射期间的现场测量.
主要成果:
- 高剂量的电子束辐射导致SiNx在与水接触时转化为氧化 (SiOx).
- 辐射导致气 (N2) 和氧气 (O2) 气体的释放.
- 在SiNx膜上形成一个扩展的氧化区域.
- 这些膜变化可以影响液体样本的测量,并可能诱导二次反应.
结论:
- 电子束诱导的SiNx膜的化学转化是LPTEM的一个重要因素.
- 实验条件应优化,以最大限度地减少SiNx转化.
- 对于高剂量实验,在数据分析过程中必须考虑电子束诱导的SiNx变化.
相关概念视频
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