An Improved Small-Signal Equivalent Circuit Model Considering Channel Current Magnetic Effect

In this letter, the channel current magnetic effect of complementary metal–oxide–semiconductor (CMOS) transistors is studied, and an improved small-signal equivalent circuit model (SSECM) is proposed. Silicon-on-insulator (SOI) CMOS transistors were fabricated and measured in a commercial 0.18- $\mu \text{m}$ process. Then, a series RL network is introduced into the classical transistor SSECM to characterize the channel current magnetic effect. To validate the model, the scattering parameters calculated by the model are compared with the measurement data. The results show that the root-mean-square error (RMSE) of the scattering parameters is less than 0.02 up to 2 GHz. And in the whole investigating frequency range, the RMSE is less than 0.063. Compared with the conventional model, which does not consider the channel current magnetic effect, the proposed model improves the accuracy in the lower frequency range remarkably.