Modeling and Verificaion of Millimeter-Wave nMOSFET up to 50 GHz in 180 nm CMOS Technology

In recent years, research on the millimeter-wave band has become popular as 5G (fifth generation) becomes more widespread. 5G uses the 28 GHz band to achieve high-speed, high-capacity wireless communications. Therefore, attempts have been made to use relatively inexpensive legacy processes in the millimeter-wave band. The problem with the legacy process is that there is no model for the millimeter-wave band. When designing a circuit with nonlinear behavior, it is necessary that the model works at least at its second harmonic frequency. In this study, we present the modeling method of an nMOSFET up to 50 GHz fabricated in the 180 nm CMOS process, and verify it using a 20 GHz oscillator with the second harmonic frequency of 40 GHz [1,2]. We show that the difference between the simulated and measured oscillation frequencies is below 5 %.