Piezoelectric RF MEMS switches and phase shifters

Piezoelectric thin films were utilized to actuate cantilevers for a radio frequency (RF) microelectromechanical system (MEMS) switches. Using lead zirconate titanate (PZT) thin films, an RF MEMS series switch was designed and fabricated. The switch operates from ??25??C to 100??C with no change in actuation voltage of 9V. The switch isolation is better than ??20 dB and the insertion loss (??S21) less than 0.5 dB from DC to 40 GHz. In addition to improvements in switch performance, a 17 GHz, 2-bit reflection phase shifter has been demonstrated using PZT shunt switches operating at 15 V. Each of the 4 phase states are demonstrated with minimal phase error and an average insertion loss of 6.8 dB with a high of 8 dB for the longest phase state (limited by substrate losses highlighted in our previous work). Correcting the substrate loss reduces the insertion loss of the long phase state to less than 2 dB.