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Updated: Jun 25, 2026
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Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope
Published on: May 28, 2016
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Nanoscale Infrared Spectroscopic Characterization of Extended Defects in 4H-Silicon Carbide
Scott G Criswell1,2, Nadeemullah A Mahadik3, James C Gallagher3
1Department of Electrical Engineering, Vanderbilt University, 2400 Highland Avenue, Nashville, Tennessee 37212, United States.
Nano Letters
|January 2, 2024
Summary
Nano-Fourier transform infrared spectroscopy (nano-FTIR) precisely characterized stacking faults in 4H-SiC. This technique identified a rare 3C-SiC stacking fault, offering new insights into semiconductor defect properties.
Area of Science:
- Materials Science
- Semiconductor Physics
- Spectroscopy
Background:
- Extended defects in wide-bandgap semiconductors impact device performance.
- Traditional characterization methods offer either spectroscopic or microscopic data.
- Nano-Fourier transform infrared spectroscopy (nano-FTIR) combines nanoscale resolution with chemical information.
Purpose of the Study:
- To demonstrate nano-FTIR's capability for characterizing extended defects in semiconductors.
- To investigate an in-grown stacking fault (IGSF) in a 4H-SiC epitaxial layer.
- To identify the stacking order of the IGSF using nanoscale spectroscopy.
Main Methods:
- Utilized nano-FTIR for nondestructive characterization.
- Achieved nanoscale spatial resolution (approximately 20 nm).
- Employed finite dipole model (FDM) simulations for comparative analysis.
Main Results:
- Observed a local spectral shift in the mid-infrared near-field response of the IGSF.
- Identified the defect stacking order as 3C-SiC (cubic) through simulations.
- Distinguished this 3C-SiC IGSF from previously reported 8H-SiC IGSFs.
Conclusions:
- Nano-FTIR provides valuable nanoscale spectroscopic insights into extended semiconductor defects.
- Understanding these defects is critical for mitigating their detrimental effects in devices.
- This study highlights nano-FTIR as a powerful tool for advanced semiconductor materials characterization.
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