Nondestructive characterization of nanoscale layered samples

Area of Science:

• Materials Science
• Nanotechnology
• Surface Science

Background:

• Multilayered nanostructures are crucial in advanced materials.
• Precise characterization of nanolayer properties is essential for their application.
• Molecular Beam Epitaxy (MBE) is a key technique for producing such structures.

Purpose of the Study:

• To nondestructively characterize multilayered Al, Co, and Ni nanolayers produced by MBE.
• To determine elemental composition, purity, sequence, roughness, density, homogeneity, and thickness.
• To evaluate the effectiveness of various characterization techniques, particularly X-ray fluorescence (XRF).

Main Methods:

• Production of multilayered samples using Molecular Beam Epitaxy (MBE).
• Nondestructive characterization via Synchrotron Radiation X-ray Fluorescence (SRXRF), micro-XRF (mu-XRF), Wavelength Dispersive X-ray Fluorescence (WDXRF), Rutherford Backscattering Spectrometry (RBS), and X-ray Reflectivity (XRR).
• Destructive characterization using Secondary Ion Mass Spectrometry (SIMS).

Main Results:

• XRF methods, including SRXRF, mu-XRF, and WDXRF, were effective in identifying elements and determining layer properties.
• Thickness measurements from XRR, RBS, SIMS, and XRF methods showed agreement within uncertainty.
• A consistent deviation from MBE preset parameters was observed, explainable by corrections in evaluation methods.

Conclusions:

• XRF techniques are valuable tools for analyzing nanolayered materials, even on commercial devices.
• The study validated the accuracy of multiple characterization methods for determining nanostructure properties.
• Refined evaluation methods and parameter redetermination resolved initial discrepancies in XRF results.