Adaptive Epitaxy of C-Si-Ge-Sn: Customizable Bulk and Quantum Structures
Omar Concepción1, Ambrishkumar J Devaiya1, Marvin H Zoellner2
1Peter Gruenberg Institute 9 (PGI-9) and JARA-Fundamentals of Future Information Technologies, Forschungszentrum Juelich, 52428, Juelich, Germany.
Advanced Materials (Deerfield Beach, Fla.)
|June 12, 2025
Summary
Introducing carbon into silicon-germanium-tin (SiGeSn) alloys creates novel direct-gap group-IV materials. These carbon-containing alloys enhance infrared light emission for advanced electronic and optoelectronic devices.
Area of Science:
- Materials Science
- Semiconductor Physics
- Optoelectronics
Background:
- Silicon-germanium-tin (SiGeSn) alloys show promise as direct-gap materials for infrared lasers.
- Extending the functionality of group IV alloys requires incorporating elements like carbon to tune properties.
Purpose of the Study:
- To explore the heteroepitaxial growth of carbon-containing silicon-germanium-tin (CSiGeSn) alloys.
- To investigate the impact of carbon incorporation on the structural, electronic, and optical properties of GeSn alloys.
Main Methods:
- Heteroepitaxial growth of CGeSn alloys using reduced-pressure chemical vapor deposition.
- Controlled incorporation of carbon using CBr4 precursor.
- Fabrication and characterization of CGeSn/GeSn multiple quantum well light-emitting diodes (LEDs).
Main Results:
- Controlled carbon incorporation (<1 at.%) and increased tin content (up to ~18 at.%) achieved.
- Carbon modulates strain, stabilizes crystal structure, and enhances optical emission.
- LEDs based on CGeSn/GeSn heterostructures exhibit enhanced near-infrared emission at 2.54 µm, sustained to room temperature.
Conclusions:
- Carbon incorporation is a viable strategy to engineer direct-gap group IV alloys.
- CSiGeSn alloys offer expanded functionality for nanoelectronics, energy harvesting, and quantum computing.
- The developed CGeSn/GeSn heterostructures demonstrate potential for advanced optoelectronic applications.
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