Emission-depth-selective auger photoelectron coincidence spectroscopy

Area of Science:

• Surface science
• Materials science
• Solid-state physics

Background:

• Understanding electron energy dissipation is crucial for surface analysis.
• Amorphous silicon surfaces present unique challenges for electron spectroscopy.
• Auger and photoelectron spectroscopy are key techniques for surface characterization.

Purpose of the Study:

• To investigate the collision statistics and energy dissipation of electrons from amorphous Si(100).
• To determine the average emission depth of individual electrons using coincidence spectroscopy.
• To establish Auger photoelectron coincidence spectroscopy (APECS) as a tool for nanoscale interface analysis.

Main Methods:

• Measuring Si 2p photoelectron and plasmon loss peaks in coincidence with Si-LVV Auger transitions.
• Analyzing the intensity variations of Si 2p plasmon loss peaks based on coincidence measurements.
• Comparing experimental results with theoretical calculations including various electron loss mechanisms and scattering.

Main Results:

• Si 2p plasmon intensity decreases when measured in coincidence with the Si-LVV Auger peak.
• This decrease is less significant when measured in coincidence with the Si-LVV plasmon loss peak.
• Experimental findings quantitatively align with theoretical models accounting for surface, volume, intrinsic losses, and elastic scattering.

Conclusions:

• Auger photoelectron coincidence spectroscopy (APECS) allows for the determination of electron emission depths.
• APECS provides a unique capability for nanoscale interface investigation.
• The study validates theoretical models for electron transport and energy loss in amorphous materials.