Novel multicontact radio frequency microelectromechanical system switch in high-power-handling applications

We report a novel multicontact radio frequency (RF) microelectromechanical system (MEMS) switch with mechanical independent switch elements and microspring contacts. The consistent contact arrangement and the robust contact design can effectively increase the contact area, reduce the current density, and therefore improve the power-/current-handling capability. The working mechanism of the switch with microspring contact is investigated by CoventorWare® simulation tools. The switch, fabricated by the Cu-Ni dual-metallic-sacrificial-layer surface micromachining, is actuated at 55 V for characterization. The closing time is 11 μs, and the opening time is 13.5 μs. The isolation is -30.9 dB at 2 GHz and -11.5 dB at 20 GHz; the insertion loss is -0.12 dB at 2 GHz and -0.22 dB at 20 GHz. The contact metal is Pt-Au, and the measured switch resistance drops from 48 to 1.2 Ω when the actuation voltage increases from 40 to 65 V. The switch element handles a current of 300 mA at 0.1 Hz. The switch is an excellent candidate for microwave applications requiring high-power handling.

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