NUMERICAL ALGORITHMS FOR MODELING MICROWAVE SEMICONDUCTOR-DEVICES

This paper presents an analysis of the numerical algorithms used to model microwave semiconductor devices. A comparison is made of the relative merits and features of the more popular finite difference schemes. A new generalized Scharfetter-Gummel formulation is presented which is compatible with drift-diffusion and energy-transport formulations, and is suitable for implementing in two-dimensional simulations on personal computers. The treatment allows for fully degenerate semiconductors, but implementation for the nondegenerate situation is easily obtained as a special case. The convergence and stability properties of the generalized scheme are discussed. The simulation of a planar submicrometre gate length GaAs MESFET is used to illustrate the application of these algorithms.