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Study of surface charges in ballistic deflection transistors
J-F Millithaler1, I Iñiguez-de-la-Torre, J Mateos
1Department of Electrical and Computer Engineering, University of Massachusetts, Lowell, MA 01854, USA.
Nanotechnology
|November 11, 2015
Summary
Accurately modeling surface charges is crucial for understanding ballistic deflection transistors (BDTs). A simple surface charge model fails under bias, necessitating a localized, adaptive model for accurate BDT operation simulation.
Area of Science:
- Semiconductor device physics
- Surface science
- Computational physics
Background:
- Ballistic deflection transistors (BDTs) offer unique electron path control.
- Accurate modeling of surface charge behavior is essential for BDT performance prediction.
- Existing models struggle to capture complex device dynamics under bias.
Purpose of the Study:
- To investigate the behavior of surface charges in BDTs at room temperature.
- To evaluate the efficacy of different surface charge models in BDT simulations.
- To determine the necessary characteristics of a surface charge model for accurate BDT operation description.
Main Methods:
- Utilizing Monte Carlo simulations to model electron transport.
- Comparing simulation results with experimental data.
- Employing and assessing various surface charge models, including constant/uniform and adaptive approaches.
Main Results:
- A simple model with constant surface charge is inadequate for biased BDTs.
- The adaptive surface charge model successfully reproduces complex device behavior.
- Surface charge distribution is strongly influenced by local carrier concentration.
Conclusions:
- Accurate BDT operation simulation requires a surface charge model that adapts locally.
- The proposed adaptive model enhances the predictive capability for BDT performance.
- Understanding surface charge dynamics is key to optimizing nanoscale electronic devices.
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