Efficient numerical methods for simulation of high-frequency active devices

Abstract

Abstract-We present two new numerical approaches for physical modeling of high-frequency semiconductor devices using filterbank transforms and the alternating-direction implicit finite-difference time-domain method. In the first proposed approach, a preconditioner based on the filter-bank and wavelet transforms is used to facilitate the iterative solution of Poisson's equation and the other semiconductor equations discretized using implicit schemes. The second approach solves Maxwell's equations which, in conjunction with the semiconductor equations, describe the complete behavior of high-frequency active devices, with larger time-step size. These approaches lead to the significant reduction of the fullwave simulation time. For the first time, we can reach over 95% reduction in the simulation time by using these two techniques while maintaining the same degree of accuracy achieved using the conventional approach.Index Terms-Alternating-direction implicit finite-difference time-domain (ADI-FDTD) method, filter-bank transforms, full-wave analysis, global modeling, high-frequency devices, preconditioning.

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