30 GHz tuned MEMS switches

• Published in: 1999 IEEE MTT-S International Microwave Symposium Digest (Cat. No.99CH36282) Vol. 4; pp. 1511 - 1514 vol.4
• Main Authors: Muldavin, J.B., Rebeiz, G.M.
• Format: Conference Proceeding Journal Article
• Language: English
• Published: IEEE 1999
• Subjects: Biomembranes; Circuit optimization; Communication switching; Electrostatics; Equivalent circuits; Micromechanical devices; Microswitches; Resonance; Switches; Voltage
• ISBN: 0780351355; 9780780351356
• ISSN: 0149-645X
• DOI: 10.1109/MWSYM.1999.780241

This paper demonstrates the use of resonant tuning in high-isolation reflective MEMS electrostatic switches. Tuned switches can achieve higher isolation and a lower pulldown voltage than a comparable single element switch. An equivalent circuit model was developed for individual shunt capacitive membrane switches and then implemented in tuned circuits. The novel cross switch was developed on a high resistivity silicon. The cross switch attained an insertion loss of less than 0.6 dB and a return loss below -20 dB from 22-38 GHz in the up-state, and a down-state isolation of 50 dB with only 1.1 pF of down-state capacitance (Cd) per element. The pulldown voltage is 15-20 V, which is much better than typical industry numbers of 28-50 V. Application areas are low-loss high-isolation communication switches at 28 GHz and automotive switches at 77 GHz.