A millimeter-wave integrated sensor for the dielectric constant characterization of pico-liter volumes of liquids

A transmission line-based integrated sensor is investigated for the dielectric constant characterization of liquids using pico-liter volumes. The sensor is manufactured using the back-end-of-line of a CMOS 0.35 μm from AMS. A simple maskless etching post-CMOS process is used to realize a cavity underneath a transmission line to insert the liquid-under-test. Measurements with a vector network analyzer demonstrate a promising method for the characterization of the dielectric constant of liquids up to 40 GHz.