Research on Key Technology of Novel RF MEMS Switch Designing and Fabricating

RF MEMS switches attract much attention in RF MEMS devices. Compared with FET and PIN switches, RF MEMS switches have much lower power consumption, lower insertion loss and higher isolation at high frequency, and can be widely used in satellite, radar, communication systems and wireless systems. This paper proposes one contact switch with single-ended cantilever beam and three kinds of capacitive switch with flexural hinge structure. The key technologies of structure design, simulation, fabrication process and test analysis are studied. COMSOL and ANSYS HFSS are used as the tools for analysis, in order to optimize the switch structure. This paper introduces the layout design and fabrication process. A method of constructing the top electrode and coplanar waveguide simultaneously is adopted to simplify the fabrication process. According to the test results, the actuation voltage of contact switches and capacitive switches are 43.5 V and 4.6~15.0 V. At the operating frequency of 4.5 GHz, the isolation of contact switches and three kinds of capacitive switches are -32.5 dB, -17.3 dB, -21.5 dB and -8.8 dB, the insertion loss are -0.47 dB, -1.4 dB, -2.0 dB and -1.2 dB respectively.