Low voltage operated piezoelectric RF MEMS switches for advanced handset applications

In this paper, fully integrated piezoelectrically actuated RF MEMS switches have been designed, fabricated, and characterized by using silicon bulk micromachining technology for advanced mobile communication systems with multi-bandlmode operatioa The proposed RF MEMS dccontact switches are comprised of four piezoelectric cantilever actuators, a contact metal pad, and a suspended CPW signal transmission line above the silicon substrate. The measured operation de bias voltages are ranged from 2.5 to 3 volts by varying the thickness of the cantilever piezoelectric actuators, which are well agreed with the simulation results. The measured isolation and insertion loss of the fabricated RFMEMS switch with a suspended CPW transmission line are 43dB and -0.23dB at a frequency of 2 GHz and an actuation voltage of 3 volts, respectively. It also has escellent RF performance characteristics at ultra-mde frequency bands. The switchlng on/off time of the fabricated switch is 4 psec at rising and 20 psec at falling actuation, respectively.