Reduction of the self-forces in Monte Carlo simulations of semiconductor devices on unstructured meshes

Computer Physics Communications (Impact Factor: 3.11). 01/2010; 181(1):24-34. DOI: 10.1016/j.cpc.2009.08.013
Source: DBLP


When using an unstructured mesh for device geometry, the ensemble Monte Carlo simulations of semiconductor devices may be affected by unwanted self-forces resulting from the particle–mesh coupling. We report on the progress in minimisation of the self-forces on arbitrary meshes by showing that they can be greatly reduced on a finite element mesh with proper interpolation functions. The developed methodology is included into a self-consistent finite element 3D Monte Carlo device simulator. Minimising of the self-forces using the proper interpolation functions is tested by simulating the electron transport in a 10 nm gate length, 6.1 nm body thick, double gate metal–oxide–semiconductor field-effect transistor (MOSFET). We demonstrate the reduction in the self-force and illustrate the practical distinction by showing I–V characteristics for the device.

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    • "The MC engine in this device simulator considers three anisotropic valleys (Γ, L, and X) with nonparabolic dispersion . The simulations of Si MOSFETs consider all relevant scattering mechanisms [14], [15] including acoustic phonons, intravalley (g-type and f -type) and intervalley (p-type) nonpolar optical phonons, interface roughness based on Ando's model [12], and ionized impurity scattering. The simulations of InGaAs MOSFETs consider the electron scattering with polar optical phonons, intervalley and intravalley optical phonons, nonpolar optical phonons, acoustic phonons, interface roughness , interface phonons at the dielectric/semiconductor interface [16], and ionized impurity scattering. "
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