Raman Scattering Study on the Influence of E-Beam Bombardment on Si Electron Lens

Area of Science:

• Materials Science
• Surface Science
• Microscopy Technology

Background:

• Microcolumns utilize micro electro-mechanical systems (MEMS) for stacked components like electron emitters and lenses.
• Electron beam passage through microcolumn apertures can lead to collisions and scattering.
• Silicon electron lenses are critical components in microcolumn devices.

Purpose of the Study:

• To investigate the effects of electron beam bombardment on silicon electron lenses.
• To analyze changes in crystallinity and surface contamination.
• To identify the origin of carbon contamination on silicon electron lenses.

Main Methods:

• Raman scattering measurements were employed to assess crystallinity.
• X-ray photoelectron spectroscopy (XPS) was used for surface analysis and chemical state determination.
• Electron beam irradiation was performed at varying acceleration voltages (0, 20, 30 keV) for 24 hours.

Main Results:

• Electron beam bombardment led to degradation of silicon electron lens crystallinity.
• Carbon-related contamination was detected on the surface and at the aperture edges of the silicon electron lens.
• Raman spectra analysis of contaminated samples confirmed carbon deposition, consistent with DC sputtering and carbon rod methods.

Conclusions:

• Electron beam bombardment negatively impacts silicon electron lens integrity.
• Carbon contamination is a significant issue affecting microcolumn performance.
• Non-destructive Raman scattering and XPS are effective methods for characterizing electron lens degradation and contamination.