The effect of work function during electron spectroscopy measurements in Scanning Field-Emission Microscopy

Area of Science:

• Material Science
• Surface Science
• Spectroscopy

Background:

• Electron spectroscopy is valuable in material science.
• Scanning Field Emission Microscopy (SFEM) integrates electron spectroscopy with scanning probe microscopy.
• A key challenge in SFEM is balancing lateral resolution with spectroscopic clarity.

Purpose of the Study:

• To demonstrate that spectroscopic information in SFEM can be obtained without compromising spatial resolution.
• To develop a new model for understanding Scanning Probe Energy Loss Spectroscopy (SPELS) measurements within SFEM.
• To explain the origin of spectral features observed in SPELS experiments.

Main Methods:

• Utilized a three-section sample: clean W(110), sub-monolayer Cs on W(110), and monolayer Cs on W(110).
• Performed Scanning Probe Energy Loss Spectroscopy (SPELS) measurements on the prepared sample.
• Developed and applied a new theoretical model to interpret SPELS data within the SFEM framework.

Main Results:

• Experimental and simulation data showed mutual agreement.
• The developed model successfully explained observed spectral features on different surfaces.
• Demonstrated that clear spectroscopic data can be achieved without significant loss of spatial resolution.

Conclusions:

• The novel understanding of SPELS resolves the trade-off between spatial resolution and spectroscopic clarity in SFEM.
• This advancement allows for high spatial resolution to be combined with meaningful spectral analysis.
• The technique offers improved insights into material surfaces using electron spectroscopy.