A unified equivalent circuit model for coplanar waveguides considering silicon substrate effects

In this paper, a unified equivalent circuit model is proposed for coplanar waveguides, which is physics-based, rather simple, and yet applicable to various resistivity substrates including very lossy substrates up to 110GHz. The unified model results are compared with Momentum simulations up to 110GHz on 8000 μ-cm, 15 μ-cm and 0.015 μ-cm silicon substrates. The unified model is also used to predict the performance of fabricated CPW lines and compared with measurement data. The model can easily be incorporated into device and circuit simulators.