A quadruple-anchored RF-MEMS switch for switched-line phase shifters

In the paper, the design, simulation and fabrication of a quadruple-anchored MEMS switch for switched-line phase shifters are presented. Swept inner bends were developed to lower the actuate voltage and suppress the stress of the deformed switch. Physical dimension of the MEMS switch is limited to 400μm × 400μm. The 3μm-thick polyimide membrane is spun between the bias and coplanar waveguides as the dielectric. The 200nm sputtered Al₂O₃ ensures the isolation of the deformed beam and the CPW. With the finite element method, the pull-in voltage of the developed switch is simulated to be 29.6V. Further, the insertion loss of the MEMS switch in up-state is lower than 1dB; the return loss is -12dB at 10GHz.