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

Computer Physics Communications (Impact Factor: 2.41). 01/2010; 181(1):24-34. DOI: 10.1016/j.cpc.2009.08.013
Source: DBLP

ABSTRACT 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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