Radio frequency power sensor based on MEMS technology with ultra low loss

A wideband 100 kHz-4 GHz power sensor, of which the basic design was presented recently by L. J. Fernandez et al. (2004), was successfully realized. The sensor is based on sensing the electrical force between the RF signal line and a suspended membrane. Optimization of the design with SONNET has resulted in measured reflection losses (S11) less than -30 dB, transmission losses (SI2) better than -0.2 dB, and a sensitivity of 80 aF/mW.