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Updated: Jul 27, 2026
09:51
Atom Probe Tomography Studies on the Cu(In,Ga)Se2 Grain Boundaries
Published on: April 22, 2013
Analysis of Three-dimensional Atom-probe Data by the Proximity Histogram.
Hellman1, Vandenbroucke, Rüsing
1Department of Materials Science and Engineering, Northwestern University, 2225 N. Campus Drive, Evanston, IL 60208-3108
Summary
Three-dimensional atom probe tomography reveals atomic-level chemical details near interfaces. This method quantifies interfacial segregation, like silver at MgO/Cu(Ag) heterophase boundaries, offering defect-specific chemical environments.
Area of Science:
- Materials Science
- Nanotechnology
- Surface Science
Background:
- Three-dimensional atom-probe tomography (3D APT) reconstructs elemental identities and positions of field-evaporated atoms.
- Analysis volumes of approximately 20 nm x 20 nm x 200 nm yield millions of atoms.
- High data density enables identification of microstructural features and chemical environments of defects.
Purpose of the Study:
- To outline a data compilation technique for generating geometrically independent composition profiles near interfaces.
- To quantitatively determine interfacial segregation of silver at a MgO/Cu(Ag) heterophase interface.
Main Methods:
- Utilizing three-dimensional atom-probe tomography (3D APT) for atomic-scale chemical analysis.
- Developing a data compilation technique for composition profiling.
- Applying the technique to a MgO/Cu(Ag) heterophase interface.
Main Results:
- Successful generation of composition profiles in the vicinity of interfaces.
- Quantitative determination of silver segregation at the MgO/Cu(Ag) heterophase interface.
- Atom-by-atom description of the chemical environment of crystallographic defects.
Conclusions:
- The described data compilation technique provides a geometrically independent method for interfacial analysis.
- 3D APT is effective for quantifying segregation and understanding chemical environments at heterophase interfaces.
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