Scalable Transmission Line and Inductor Models for CMOS Millimeter-Wave Design

A new equivalent-circuit model for transmission lines and inductors on silicon is proposed. The SPICE-compatible model is suitable for time-domain simulators. It is able to fit the frequency-dependent behavior of the RLGC parameters well into the millimeter-wave range. The model is extracted from electromagnetic simulations with a simple analytic procedure with no need for tuning or optimization. A method for making the model scalable with both line length and width (or inductor diameter) is proposed. Based on this new model, a scalable measurement deembedding methodology is proposed, that can greatly reduce wafer area needed for test and deembedding structures. The fully scalable model results are compared with measurements of devices fabricated in a 90 nm CMOS process.