Wideband RF-MEMS shunt switches with high reliability for microwave and millimeter wave applications

Summary form only give, as follows. An ultra wideband RF-MEMS shunt switch with a PZT/HfO₂ stacked insulator has been developed for microwave and millimeter wave applications. The both of the conjunctive dielectric constant, 80, of PZT(r=800)/HfO₂(r=20) stack layer and a match circuit contribute to high isolation of -30 dB at ultra wideband from 1 GHz to 50 GHz frequencies. The increase of the trap density in the HfO₂ layer caused from carrier injection from the electrode of the switch into the insulator is smaller than that of silicon nitride (Si ₃N₄) under constant voltage stress resulting in the suppression of the stiction of the switch. The percolation and annealing model is analytically introduced to explain the lower trap density and higher stress-endurance characteristics of HfO₂ than Si₃N₄ usually used as switch insulator. The projected lifetime of the witch with the stacked layer is more than 10 years. This is the best data ever reported