Development of a slow-wave MEMS phase shifter on CMOS technology for millimeter wave frequencies
We propose a slow-wave MEMS phase shifter that can be fabricated using the CMOS back-end and an additional maskless post-process etch. The tunable phase shifter concept is formed by a conventional slow-wave transmission line. The metallic ribbons that form the patterned floating shield of this type of structure are released to allow motion when a control voltage is applied, which changes the characteristic impedance and the phase velocity. For this device a quality factor greater than 40 can be maintained, resulting in a figure of merit on the order of 0.7dB/360 and a total area smaller than 0.14mm2 for a 60-GHz working frequency.
slow-wave phase shifter millimeter wave cmos mems