Subatomic Distortion of Surface Monolayer Lattice Visualized by Moiré Pattern

Area of Science:

• Surface Science
• Materials Science
• Nanotechnology

Background:

• Understanding thin film properties requires mapping local lattice distortion.
• Direct microscopic methods lack sufficient resolution for detecting local distortions.
• Accurate characterization of thin films is crucial for advanced material applications.

Purpose of the Study:

• To develop a high-resolution method for estimating local lattice distortion in monatomic films.
• To visualize and analyze local distortions on a hexagonal iron nitride monolayer.
• To correlate lattice distortion with the location of subsurface impurities.

Main Methods:

• Utilized topographic scanning tunneling microscopy (STM) to obtain moiré patterns.
• Analyzed moiré pattern low centers of hexagonal iron nitride on Cu(111).
• Calculated local distortion by comparing experimental center positions to ideal positions.

Main Results:

• Successfully visualized local lattice distortion with high resolution using STM moiré patterns.
• The developed method accurately estimated displacement from ideal lattice positions.
• Identified a preferential location of subsurface impurities in highly distorted areas.

Conclusions:

• Moiré patterns in STM topographic images provide a high-resolution tool for mapping local lattice distortion.
• This approach enables the visualization of lattice imperfections and their correlation with impurities.
• The demonstrated technique is broadly applicable to various thin film-substrate systems.