Effect of frequency in the 3D integration of a PZT-actuated MEMS switch using a single crystal silicon asymmetric beam

This paper presents the effect of frequency of radio frequency microelectromechanical system (RF MEMS) 3D integration with an actual device. A piezoelectric transducer (PZT)-actuated RF MEMS switch that uses a single crystal silicon asymmetric beam was designed, fabricated, and evaluated. We successfully drove a stiff beam (with spring constant >; 2,000 N/m) despite a low voltage (<;15 V). The switch lifetime was 4 × 107 cycles at low contact resistance and more than 1 × 109 cycles for the PZT actuator. The overall insertion loss and isolation were -0.3 dB and -25 dB, respectively, up to 5GHz. The effect of frequency of 3D integration was simulated with an RF MEMS switch and a ground plane placed over it. We discovered that a 3D IC comprising a control IC and an RF MEMS switch with a distance of more than 80 μm was successfully integrated.