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Updated: Dec 14, 2025
10:57
Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
18.8K
Impact and behavior of Sn during the Ni/GeSn solid-state reaction
Andrea Quintero1,2, Patrice Gergaud1, Jean-Michel Hartmann1
1Univ. Grenoble Alpes, CEA, LETI, F-38000 Grenoble, France.
Journal of Applied Crystallography
|July 21, 2020
Summary
Tin (Sn) incorporation into nickel (Ni) intermetallic phases during solid-state reactions (SSR) in GeSn-based Si photonics was studied. Sn segregation at grain boundaries impedes Ni(GeSn) phase growth, requiring higher temperatures for contact formation.
Area of Science:
- Materials Science
- Semiconductor Physics
- Nanotechnology
Background:
- Nickel-based intermetallics are crucial for efficient contacts in Germanium-Tin (GeSn)-based Silicon (Si) photonic devices.
- The precise role of Tin (Sn) during the Nickel (Ni)/GeSn solid-state reaction (SSR) remains incompletely understood.
Purpose of the Study:
- To comprehensively analyze Tin (Sn) segregation during the Ni/GeSn SSR.
- To elucidate the impact of Sn on intermetallic phase formation and diffusion kinetics.
Main Methods:
- Utilized in situ X-ray diffraction to monitor phase evolution.
- Employed cross-section transmission electron microscopy for microstructural analysis.
- Applied energy-dispersive X-ray spectrometry and electron energy-loss spectroscopy for atomic mapping of Sn distribution.
Main Results:
- Observed Sn incorporation into the intermetallic phases during SSR.
- Identified Sn segregation initially at grain boundaries (GBs), subsequently migrating to the surface.
- Demonstrated that Sn accumulation at GBs hinders atom diffusion, delaying Ni(GeSn) phase growth.
Conclusions:
- Higher thermal budgets are necessary for forming contacts in high-Sn-content photonic devices due to Sn segregation.
- The observed delay in Ni(GeSn) phase growth could impact device fabrication and thermal stability.
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