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Updated: Sep 19, 2025
10:31
Plasma-assisted Molecular Beam Epitaxy of N-polar InAlN-barrier High-electron-mobility Transistors
Published on: November 24, 2016
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Interfacial Polarization Switching in Al0.92Sc0.08N/GaN Heterostructures Grown by Sputter Epitaxy.
Niklas Wolff1,2, Georg Schönweger1,3, Md Redwanul Islam1
1Department of Material Science, Kiel University, Kaiserstr. 2, D-24143, Kiel, Germany.
Summary
Highly coherent ferroelectric aluminum scandium nitride (AlScN) thin films grown on gallium nitride (GaN) show domain switching mechanisms crucial for advanced transistors and memory devices.
Area of Science:
- Materials Science
- Solid State Physics
- Nanotechnology
Background:
- Integration of ferroelectric AlScN onto GaN is key for novel high-power transistors and memory devices.
- Understanding ferroelectric domain structures and their electrical impact is essential for device optimization.
Purpose of the Study:
- To demonstrate sputter epitaxy of highly coherent Al0.92Sc0.08N thin films on GaN.
- To investigate ferroelectric domain structures and switching mechanisms in Al0.92Sc0.08N/GaN heterostructures.
Main Methods:
- Sputter epitaxy for thin film growth.
- Scanning transmission electron microscopy (STEM) for domain imaging.
- Electron energy loss spectroscopy (EELS) for electronic structure analysis.
Main Results:
- Demonstrated highly coherent Al0.92Sc0.08N films on GaN approaching lattice-matching.
- Revealed polar domains and interfacial switching mechanism initiating polarization inversion.
- Identified persistent M-polarity domains at the Pt electrode interface after switching.
Conclusions:
- Insights into ferroelectric domain location and atomic structure in sputter-deposited Al0.92Sc0.08N/GaN.
- Comparison with MOCVD-grown films aids understanding of defect structures.
- Knowledge supports development of future non-volatile memory and transistor devices through interface and defect engineering.
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