Multimass Three-Dimensional Velocity Map Imaging from Surfaces

Area of Science:

• Surface science
• Analytical chemistry
• Physical chemistry

Background:

• Understanding ion formation dynamics is crucial for surface analysis.
• Existing methods may lack the resolution for detailed velocity distribution measurements.

Purpose of the Study:

• To present a new multimass ion imaging method for surface scattering studies.
• To demonstrate the capability of measuring full three-dimensional velocity distributions of multiple ions.
• To investigate the dynamics of secondary ion formation.

Main Methods:

• Utilizes a multimass ion imaging technique with the sample on the repeller plate.
• Employs velocity mapping of ions along the surface normal.
• Uses a fast imaging camera for position and time-of-flight measurements.
• Applies the method to secondary ion mass spectrometry (SIMS) experiments with C60+ impact.

Main Results:

• Successfully measured the half-Newton spheres and full 3D velocity distributions of multiple ions.
• Provides insights into the dynamics of secondary ion formation.
• Demonstrates the technique's effectiveness in SIMS experiments.

Conclusions:

• The developed 3D velocity map imaging technique is a powerful tool for surface dynamical measurements.
• The method is suitable for pulsed ion generation or extraction scenarios.
• Advances the understanding of ion-surface interactions and secondary ion formation processes.