A Generic, Scalable Model Applicable to MIM Capacitors of Arbitrary Electrical Length

Several metal-insulator-metal (MIM) thin film capacitor models suitable for MMIC design are available in commercial microwave circuit simulators and GaAs foundry process design kits. Although these models are in general accurate for series capacitors arbitrary electrical length, they are somewhat less useful for shunt capacitors over grounding substrate vias. Typically the bottom plate is not available as a ground connection node and in some cases exhibit non-physical anomalous resonance that does not occur in the actual capacitor. It is demonstrated that the coupled line (CL) capacitor model does not exhibit anomalous resonance, agrees with EM simulation for capacitors of significant electrical length, and features some advantages with regard to connection to the top and bottom plates of the capacitor