Tunable MEMS capacitor: influence of fluids

摘要

The effect of a dielectric liquid on the tunability of capacitor operating in RF domains is evaluated. The RF measurement shows a high variation of the resonant frequency accompanied with a low insertion loss. Moreover, the fluid positions between electrodes modify the capacitance value up to Tr = 6660% at 600 MHz. The quality factor decreases in response of water filling from Qmax = 51.9 when it is empty to Qmin = 1.49 when it is fully filled. According to the finite-element method analysis, the change of the dielectric permittivity influences the capacitor performances. Essentially, the tuning range of the capacitance and the quality factor could reach, respectively: Tr = 7660% and Qmin = 35.