Linear and nonlinear characteristics of the silicon CMOS monolithic 50-Ω microwave and RF control element

Radio-frequency (RF) control elements using silicon CMOS technology are investigated as an alternative to traditional PIN diode and GaAs MESFET control devices. Silicon CMOS RF control elements are attractive because of their potential in all-silicon monolithic CMOS solutions for completely integrated baseband and RF functions in low-cost wireless systems. Results of the study show that silicon CMOS switches can be designed to rival the insertion loss and isolation of gallium arsenide switches at low frequencies. Data are presented that show less than 1 dB insertion loss and isolation of greater than 50 dB at low frequencies for a variety of silicon CMOS fabrication technologies. A model for a distortion intercept point in MOS switches is presented and validated with experimental measurements.