Accurate computer-aided modeling of multilayer GaAs microstrip lines using a spectral-domain method

Multilayer microstrip lines are an integral part of MMIC. This paper presents an analysis of multilayer GaAs microstrip lines using a spectral-domain method (SDM), taking into account the effect of the variation in the thickness of various layers of substrates on the characteristic impedance and the effective dielectric constant of the line. Some of the theoretical results are validated by the measured results on three-layer GaAs microstrip lines, showing a close agreement within a 1% deviation over a large frequency range up to 20 GHz. The proposed CAD model is expected to provide an economical and fast CAD procedure for GaAs-MMIC foundries. (C) 2003 Wiley Periodicals, Inc.