GOOD-SIM: a generic object-oriented device simulator, based on the hydrodynamic model and including non-parabolic band structure effects

Abstract

In this paper we present the GOOD-SIM simulation program, which solves the generalized hydrodynamic equations (HDEs) in semiconductor devices, including non-parabolic band structure effects. GOOD-SIM simulates the electrical characteristics of arbitrary 2D structures, under user-specified conditions. The program is based on a novel device class library (DCL) and a 2D discretization scheme for the HDEs. which is fully compatible with the Scharfetter-Gummel (SG) difference approximation for the drift-diffusion model (DDM). The full compatibility of the discretization scheme permits the full use of available DDM solvers. The simulator is equipped with a visual device editor, a visual grid editor and a macro-compiler that enables the user to edit new physical models for the different device parameters (like carrier drift mobility, impact ionization rate and injection probability) in the run-time. The CPU time and memory required, though being relatively higher than those needed for the DDM, are still very small compared to the corresponding computer resources required for the direct solution of the Boltzmann transport equation (BTE). Because of its object-oriented nature, GOOD-SIM can be easily extended in 3D by the appropriate modification of the Cdiscreteization class, which incorporates the spatial distributions of main variables over discrete elements. New balance equations can also be added by the modification of the CEquation class, which incorporates the hydrodynamic transport model.