Investigations of rf shunt airbridge switches among different environmental conditions

This paper reports on extensive investigations on capacitive radio frequency (rf) microelectromechanical systems (MEMS) shunt airbridge switches especially among different environmental conditions. Single airbridge switches yield an insertion loss lower than 0.28 dB at 35 GHz and an isolation down to −38 dB at 35 GHz. The capacitance ratio C on/ C off is approximately 60 (best case). The measured temperature dependency of the pull-in voltage was −0.3 V/°C in the temperature range from −25 to 75°C. The measured switching time was 11 μs and the release time 7 μs. More than 5×10 4 switching cycles could be performed in a non-stabilised environment. For optimised switches no self-closing is observed up to 1 W rf power at 30 GHz. The measurement results are in good agreement with the simulated values.