Comparison of C-V measurement methods for RF-MEMS capacitive switches

The applicability of several capacitance-voltage measurement methods is investigated for the on-wafer characterization of RF-MEMS capacitive switches. These devices combine few-picofarad capacitance with a high quality factor. The standard quasistatic and high-frequency measurements are employed, as well as the recently introduced very-low-frequency method. S11 is measured by a network analyzer to calculate the capacitance of the device from radio-frequency measurements. Significant differences are found around the pull-in and pull-out voltages.