INDUCTIVELY-TUNED K/KA BAND RF MEMS CAPACITIVE SWITCHES

This paper designs, fabricates, and analyzes an inductively-tuned K/Ka band RF MEMS (Radio frequency micro-electro-mechanical-systems) capacitive switches. The MEMS switch employs a defect ground structure (DGS) and an air bridge. Two different MEMS switches, one with air bridges and the other not, are designed. Surface current distribution results of MEMS switches in different states are simulated and discussed. A novel actuation voltage’s calculation approach of MEMS switch is proposed. Measured results indicate that the type MEMS switch’s actuation voltage is 20 V. For the MEMS switch without air bridges, the isolation is more than 15 dB from 12.5 to 20 GHz, and the insertion loss is less than 0.28 dB up to 20 GHz. For the MEMS switch with integrated air bridges, the isolation is more than 15 dB from 18.3 to 40 GHz, and the insertion loss is less than 0.64 dB up to 40 GHz. Circuit models and measured results of the proposed MEMS switches show good agreements. The pull-in and release time of this switch are 99 μs and 49 μs, and the lifetime of this type of switch is more than three million.