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Generalized lucky-drift model for impact ionization in semiconductors with disorder
O Rubel1, A Potvin, D Laughton
1Thunder Bay Regional Research Institute, Thunder Bay, ON, Canada. rubelo@tbh.net
Summary
A new lucky-drift model explains avalanche effects in disordered semiconductors, incorporating optical phonon and disorder scattering. This model accurately predicts impact ionization in amorphous selenium.
Area of Science:
- Condensed matter physics
- Semiconductor physics
Background:
- Avalanche phenomena are observed in amorphous semiconductors.
- Existing models may not fully capture transport in disordered materials.
Purpose of the Study:
- To extend the lucky-drift model for disordered semiconductors.
- To explain avalanche effects and impact ionization.
Main Methods:
- Generalized the lucky-drift model.
- Included inelastic (optical phonon) and elastic (disorder potential) scattering.
- Verified the analytical solution with kinetic Monte Carlo simulations.
Main Results:
- Developed an analytical solution for carrier transport.
- Simulations confirmed the model's validity.
- Interpreted experimental data for amorphous selenium.
Conclusions:
- The extended lucky-drift model successfully describes avalanche phenomena in disordered semiconductors.
- The model provides a framework for understanding impact ionization coefficients.
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