A De-Embedding Method for Small-Signal Modeling Up to 110 GHz With Improved Pad Structure Model

In this letter, an enhanced pad structure model is proposed to improve the conventional open-short de-embedding method for high-frequency applications. This model considers high-frequency electromagnetic coupling between input and output ports. Three coupling paths due to the nonideal properties of the medium are described. Compared with the conventional pad model, the proposed model reduces the average relative root mean square error (RRMSE) from 43.9% to 11.8% up to 110 GHz. To further validate the pad model application, a transistor model is constructed to depict the small-signal performance based on a 28-nm-bulk CMOS process. The model calculation results show good agreement with the de-embedded measurement results.