Low energy nano diffraction (LEND) - A versatile diffraction technique in SEM.

Area of Science:

• Materials Science
• Solid State Physics
• Electron Microscopy

Background:

• Electron diffraction is crucial for material characterization, commonly used in Transmission Electron Microscopy (TEM).
• Diffraction techniques in Scanning Electron Microscopy (SEM) are less developed, particularly on-axis transmission diffraction.
• Existing SEM diffraction methods like electron backscatter diffraction have limitations for certain analyses.

Purpose of the Study:

• To develop and present a versatile setup for on-axis electron diffraction in SEM.
• To enable nano-beam diffraction pattern acquisition at low electron energies.
• To introduce the technique named Low Energy Nano Diffraction (LEND).

Main Methods:

• Implementation of a fluorescent screen and an in-vacuo camera within an SEM.
• Acquisition of spot-like nano-beam diffraction patterns from thin samples.
• Utilizing electron energies as low as 500 eV for diffraction analysis.
• Performing single-position measurements and area-integrated diffraction patterns.
• Demonstrating 4D-STEM diffraction mappings.

Main Results:

• Successful implementation of Low Energy Nano Diffraction (LEND) in SEM.
• Acquisition of diffraction patterns from various materials including gold, silicon, graphene, and other 2D materials.
• Demonstration of LEND's capability for both single-point and area-averaged analysis.
• Validation of 4D-STEM diffraction mapping capabilities with LEND.

Conclusions:

• LEND provides a simple yet versatile method for on-axis electron diffraction in SEM.
• The technique allows for detailed crystallographic analysis of thin films and 2D materials at low energies.
• Integrating LEND into SEM enhances analytical capabilities, enabling comprehensive studies within a single instrument.