Analytical Model and Parameter Extraction to Account for the Pad Parasitics in RF-CMOS

A model which considers the pad parasitic effects when performing on-wafer S-parameter measurements on microwave devices fabricated on silicon substrates is presented. The model parameters are directly determined using a simple and analytical measurement-based method, allowing the electrical representation of the complete test structure using an equivalent circuit. The validity of the model is verified by achieving excellent agreement between simulated and experimental data up to 55GHz. In addition, a recently reported simplified deembedding procedure is improved and compared to a conventional one to study its validity as frequency increases.