A domain decomposition method for silicon devices

A mesoscopic/macroscopic model for self-consistent charged transport under high field scaling conditions corresponding to drift-collisions balance was derived by Cercignani, Gamba, and Lever-more in [4]. The model was summari zed in relationship to semiconductors in [2]. In [3], a conceptual domain d ecomposition method was implemented, based upon use of the drift-diffusion model in highly-doped regions of the device, and use of the high-field mode l in the channel, which represents a (relatively) lightly-doped region. The hydrodynamic model was used to calibrate interior boundary conditions. The material parameters of GaAs were employed in [3]. This paper extends the approach of [3]. Benchmark comparisons are described for a Silicon n(+) - n - n(+) diode. A global kinetic model is simulated with Silicon parameters. These simulation s are sensitive to the choice of mobility/relaxation. An elementary global domain decomposition method is presented. Mobilities a re selected consistently with respect to the kinetic model. This study unde rscores the significance of the asymptotic parameter eta defined below, as the ratio of drift and thermal velocities as a way to measure the change in velocity scales. This parameter gauges the effectiveness of the high field model.