Reliability test of a RF MEMS varactor based on a double actuation mechanism

This paper presents the design and reliability tests of a novel micro-electro mechanical varactor based on a double actuation mechanism allowing for overall capacitive ratio Cr of 5.2 and continuous capacitive ratio Cr* of 2.6. The device has been modeled in ANSYS® multiphysics environment and manufactured by using the 8-masks FBK-irst RF MEMS process. The performance was tested on 10 samples showing good mechanical reproducibility and negligible capacitance ratios variation (Cr =5.2 ± 5%, Cr*=2.6 ± 4%). Self-biasing tests have been performed by applying an equivalent Vrms on the RF central conductor, showing an insignificant capacitance ratio variation up to 13.5Vrms. Finally, cycling test was performed on the DUT up to 108 cycles, showing negligible variation of the capacitance.