A novel electrothermally actuated RF MEMS switch for wireless applications

This paper presents a new type of thermally actuated switch for wireless communication system operated at low gigahertz frequencies. The switch is driven by a metal electrothermal actuator, which can generate large displacement and high contact force at lower temperatures. The MEMS switch utilizing the parallel four-beam actuator requires driving voltage of 0.07 V for an 8 μm displacement. RF performances are improved by suspending the structure 25 μm from the substrate using MetalMumps process. An ON state insertion loss of -0.27 dB at 10 GHz and an OFF state isolation of -40 dB at 10 GHz are achieved on low resistivity silicon substrate.