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arXiv · 0902.3514

A discontinuous Galerkin solver for Boltzmann Poisson systems in nano devices

Yingda Cheng·Irene M. Gamba·Armando Majorana·Chi-Wang Shu
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Abstract

In this paper, we present results of a discontinuous Galerkin (DG) scheme applied to deterministic computations of the transients for the Boltzmann-Poisson system describing electron transport in semiconductor devices. The collisional term models optical-phonon interactions which become dominant under strong energetic conditions corresponding to nano-scale active regions under applied bias. The proposed numerical technique is a finite element method using discontinuous piecewise polynomials as basis functions on unstructured meshes. It is applied to simulate hot electron transport in bulk silicon, in a silicon $n^+$-$n$-$n^+$ diode and in a double gated 12nm MOSFET. Additionally, the obtained results are compared to those of a high order WENO scheme simulation and DSMC (Discrete Simulation Monte Carlo) solvers.

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Yingda Cheng, Irene M. Gamba, Armando Majorana, Chi-Wang Shu. 2009-02-20. A discontinuous Galerkin solver for Boltzmann Poisson systems in nano devices. https://doi.org/10.1016/j.cma.2009.05.015

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