Abstract
MEMS switches based on a dual-mode actuation scheme that simultaneously allows for large standoff heights and low clamping voltages have been designed and fabricated. These devices are based on the use of a transient external magnetic field to bring the actuating portion of the switch close to a dielectric-coated clamping electrode, followed by application of an electrostatic clamping voltage to keep the switch closed. Since the clamping voltage is applied when the switch is closed, this voltage can be relatively small. This approach is particularly attractive for RF applications such as arrays of switches in reconfigurable aperture antennas. The arrays of switches are simultaneously closed by the magnetic field generated by an external magnetic source, then selected switches are clamped by electrostatic force using low voltages to maintain the ON state. Their utility in such an array has been demonstrated and several different design variations have been explored to improve switch performance. Contact resistance as low as 0.37 Ω has been achieved, with actuating field strength of 40 Gauss. These switches possess a large open state air gap (25 μm), and are able to pass high currents in excess of 1 A under low frequency or DC operation. The large OFF state impedance allows for their usage in switching applications in RF devices. Their high frequency functionality has been tested to find that their open-state impedance was identical to that of a perfect open up to 9 GHz and their RF reconfigurability has been demonstrated in a monopole/dipole test bed.
Similar content being viewed by others
References
Aberle JT, Oh S, Auckland DT, Rogers SD (2003) Reconfigurable antennas for wireless devices. IEEE Antennas Propag Mag 45:148–154. doi:10.1109/MAP.2003.1282191
Almeida L, Ramadoss R, Jackson R, Ishikawa K, Yu Q (2006) Study of the electrical contact resistance of multi-contact MEMS relays fabricated using the MetalMUMPs process. J Micromech Microeng 16:1189–1194. doi:10.1088/0960-1317/16/7/011
Anagnostou D, Chryssomallis MT, Lyke JC, Christodoulou CG (2003) Re-configurable Sierpinski gasket antenna using RF-MEMS switches. In: IEEE international symposium antennas Propagation Society, pp 375–378
Bernstein JJ, Taylor WP, Brazzle JD, Corcoran CJ, Kirkos G, Odhner JE, Pareek A, Waelti M, Zai M (2004) Electromagnetically actuated mirror arrays for use in 3-D optical switching applications. J Microelectromech Syst 13(3):526–535. doi:10.1109/JMEMS.2004.828705
Brown ER (1998) RF-MEMS switches for reconfigurable integrated circuits. IEEE Trans Microw Theory Tech 46(11):1868–1880. doi:10.1109/22.734501
Chan R, Lesnick R, Becher D, Feng M (2003) Low-actuation voltage RF MEMS shunt switch with cold switching lifetime of 7 billion cycles. J Microelectromech Syst 12:713–719. doi:10.1109/JMEMS.2003.817889
Cho I, Song T, Baek S, Yoon E (2005) A low-voltage push-pull SPDT RF MEMS switch operated by combination of electromagnetic actuation and electrostatic hold. In: Proceedings of the 18th IEEE international conference on micro electro mechanical systems, pp 32–35
Chu C, Shih W, Chung S, Tsai H, Shing T, Chang P (2007) A low actuation voltage electrostatic actuator for RF MEMS switch applications. J Micromech Microeng 17:1649–1656. doi:10.1088/0960-1317/17/8/031
Craig RR (1996) Mechanics of materials, 1st edn. Wiley, New York, pp 377–389
De SK, Aluru NR (2004) Full-lagrangian schemes for dynamic analysis of electrostatic MEMS. J Microelectromech Syst 13(5):737–758. doi:10.1109/JMEMS.2004.835773
Judy JW, Muller RS (1996) Magnetic microactuation of torsional polysilicon structures. Sens Actuators A Phys 53(1):392–396
Judy JW, Muller RS, Zappe HH (1995) Magnetic microactuation of polysilicon flexure structures. J Microelectromech Syst 4:162–169. doi:10.1109/84.475542
Kruglick EJJ, Pister KSJ (1999) Lateral MEMS microcontact considerations. J Microelectromech Syst 8:264–271. doi:10.1109/84.788630
Lee H, Park J, Park J, Nam H, Bu J (2005) Design, fabrication and RF performances of two different types of piezoelectrically actuated ohmic MEMS switches. J Micromech Microeng 15:2098–2104. doi:10.1088/0960-1317/15/11/015
Muldavin JB, Rebeiz GM (2000) High-isolation CPW MEMS shunt switches. IEEE Trans Microw Theory Tech 48(6):1045–1052. doi:10.1109/22.904743
Niarchos D (2003) Magnetic MEMS: key issues and some applications. Sens Actuators A Phys 109(1):166–173. doi:10.1016/j.sna.2003.09.010
Pattona ST, Zabinski JS (2005) Fundamental studies of Au contacts in MEMS RF switches. Tribol Lett 18:215–230. doi:10.1007/s11249-004-1778-3
Pringle LN, Harms PH, Blalock SP, Kiesel GN, Kuster EJ, Friederich PG, Prado RJ, Morris JM, Smith GS (2004) A reconfigurable aperture antenna based on switched links between electrically small metallic patches. IEEE Trans Antenna Propag 52:1434–1445. doi:10.1109/TAP.2004.825648
Ruan M, Shen J, Wheeler CB (2001) Latching micromagnetic relays. J Microelectromech Syst 10(4):511–517. doi:10.1109/84.967373
Schaffner JH, Loo RY, Sievenpiper DF, Dolezal FA, Tangonan GL, Colburn JS, Lynch JJ, Lee JJ, Livingston SW, Broas RJ, Wu M (2000) Reconfigurable aperture antennas using RF MEMS switches for multi-octave tunability and beam steering. In: IEEE international symposium antennas and propagation society, pp 321–324
Taylor WP, Brand O, Allen MG (1998) Fully integrated magnetically actuated micromachined relays. J Microelectromech Syst 7:181–191. doi:10.1109/84.679353
Vinoy KJ, Varadan VK (2001) Design of reconfigurable fractal antennas and RF-MEMS for space-based systems. Smart Mater Struct 10:1211–1223. doi:10.1088/0964-1726/10/6/310
Zendejas JM, Gianvittorio JP, Rahmat-Samii Y, Judy JW (2006) Magnetic MEMS reconfigurable frequency-selective surfaces. J Microelectromech Syst 15:613–623. doi:10.1109/JMEMS.2005.863704
Acknowledgments
This work was supported by the Defense Advanced Research Projects Agency. Valuable technical discussion with Dr. Lon Pringle of the Georgia Tech Research Institute is gratefully acknowledged.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Choi, Y., Kim, K. & Allen, M.G. High standoff dual-mode-actuation MEMS switches. Microsyst Technol 15, 777–787 (2009). https://doi.org/10.1007/s00542-009-0805-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00542-009-0805-6