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Building Langmuir Probes and Emissive Probes for Plasma Potential Measurements in Low Pressure, Low Temperature Plasmas
Published on: May 25, 2021
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Charge kinetics across a negatively biased semiconducting plasma-solid interface.
K Rasek1, F X Bronold1, H Fehske1
1Institut für Physik, Universität Greifswald, 17489 Greifswald, Germany.
Physical Review. E
|May 20, 2022
Summary
This study reveals that hot carriers drive current across semiconductor-plasma interfaces, challenging the perfect absorber model. Understanding electron microphysics is crucial for accurate charge transport analysis.
Area of Science:
- Plasma physics
- Semiconductor physics
- Materials science
Background:
- Investigating plasma-solid interfaces is key for electronic device applications.
- Understanding charge transport mechanisms at these interfaces is complex.
- Existing models may not fully capture semiconductor interface behavior.
Purpose of the Study:
- To investigate self-consistent ambipolar charge kinetics at a negatively biased semiconducting plasma-solid interface.
- To analyze the current-voltage characteristics of a germanium layer under plasma exposure.
- To visualize charge carrier behavior and distributions within the semiconductor layer.
Main Methods:
- Numerical calculation of current-voltage characteristics.
- Analysis of spatially and energetically resolved charge carrier fluxes and distributions.
- Modeling a thin germanium layer with nonpolar electron-phonon scattering interfacing with argon plasma.
Main Results:
- The semiconductor's electron microphysics significantly impacts the current-voltage characteristic.
- Charge transport is mediated by relatively hot carriers.
- The perfect absorber model is inadequate for describing charge transport across semiconducting interfaces.
Conclusions:
- Hot carrier transport is a critical factor at plasma-semiconductor interfaces.
- The perfect absorber model requires revision for semiconducting interfaces.
- Further refinement of semiconductor band structure models and inclusion of scattering processes are needed for quantitative accuracy.
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