A comparative analysis of efficiency and reliability of capacitive micro-switches with initially curved electrodes

  • Bahman Mostafaei
  • Mohammad FathalilouEmail author
  • Ghader Rezazadeh
  • Aydin Azizi
Technical Paper


Enhancement of both efficiency and reliability of MEMS structures has always been an interesting and even essential issue for research community. This paper provides a comparative investigation in this field focusing on the role of initially curved electrodes of capacitive micro-switches. Four models have been introduced by appliance of curved microbeams as either upper or lower electrodes of a capacitive MEMS switch, as well as the conventional base model with straight both electrodes. By introducing a mathematical model and appropriate numerical procedure, the contact area between two electrodes, which has direct effect on the reliability has been estimated using Hertz relation for all models. The electromechanical coupling factor which is related to the efficiency of the switch has been calculated considering the stored mechanical and electrical energy of the system. The results have shown that by appliance of an initial curvature to the both electrodes, the estimated contact area can increase up to 279% compared to the conventional switches. Also, a switch with straight moveable electrode and curved substrate exhibits an increase in coupling factor up to 24% compared to the base model, while increasing the pull-in voltage of the switch.



  1. Attar A, Fathalilou M, Rezazadeh G (2019) Mechanical behavior of a cylindrical capacitive micro-switch compared to a straight beam type. J Mech Sci Technol 33:2241–2248CrossRefGoogle Scholar
  2. Bao M, Wang W (1996) Future of microelectromechanical systems (MEMS). Sens Actuators A Phys 56:135–141CrossRefGoogle Scholar
  3. Batra RC, Porfiri M, Spinello D (2007) Review of modeling electrostatically actuated microelectromechanical systems. Smart Mater Struct 16:23–31CrossRefGoogle Scholar
  4. Becher D, Chan R, Hattendorf M, Feng M (2002) Reliability study of low-voltage RF MEMS switches. In: Proceedings of GaAs Mantech, pp 7–54Google Scholar
  5. Beer FP, Johnston ER (2004) Mechanics of materials, 3rd edn. McGrawHill, New YorkGoogle Scholar
  6. Burns D, Zook J, Horning R, Herb W, Guckel H (1995) Sealed-cavity resonant microbeam pressure sensor. Sens Actuators A Phys 48:179–186CrossRefGoogle Scholar
  7. Caronti A, Carotenuto R, Pappalardo M (2002) Electromechanical coupling factor of capacitive micromachined ultrasonic transducers. J Acoust Soc Am 113(1):279–288CrossRefGoogle Scholar
  8. Costa J (2009) RF MEMS switch technology for radio front end applications. In: Proceedings of IEEE MTT-S international microwave symposiumGoogle Scholar
  9. Czaplewski DA, Nordquist CD, Dyck CW, Patrizi GA, Kraus GM, William DC (2012) Lifetime limitations of ohmic, contacting RF MEMS switches with Au, Pt and Ir contact materials due to accumulation of ‘friction polymer’ on the contacts. J Micromech Microeng 22:105005CrossRefGoogle Scholar
  10. Fathalilou M, Rezazadeh G, Mohammadian A (2019) Stability analysis of a capacitive micro-resonator with embedded pre-strained SMA wires. Int J Mech Mater Des (online available)Google Scholar
  11. Hunt FV (1982) Electroacoustics. The analysis of transduction, and its historical background. AIP, Woodbury, NYGoogle Scholar
  12. Judy WJ (2001) Microelectromechanical systems (MEMS): fabrication, design and applications. Smart Mater Struct 10:1115–1134CrossRefGoogle Scholar
  13. Kim JM, Lee S, Baek CW, Kwon Y (2008) Cold and hot-switching lifetime characterizations of ohmic-contact RF MEMS switches. IEICE Electron Express 5(11):418–423CrossRefGoogle Scholar
  14. Kinsler LE, Frey AR, Coppens AB, Sanders JV (1982) Fundamentals of acoustics. Wiley, New YorkGoogle Scholar
  15. Kumar J, Tetteh EA, Braineard E (2014) A study of why electrostatic actuation is preferred and a simulation of an electrostatically actuated cantilever beam for MEMS applications. IJESET 6(5):441–446Google Scholar
  16. Kwon H, Choi D-J, Park J-H, Lee H-C, Park Y-H, Kim Y-D, Nam H-J, Joo Y-C, Bu J-U (2007) Contact materials and reliability for high power RF-MEMS switches. In: Proceedings of the 20th IEEE international conference on micro electro mechanical systems, pp 231–234Google Scholar
  17. Kwon H, Park J, Lee H, Choi D, Park Y, Nam H, Joo Y (2008) Investigation of similar and dissimilar metal contacts for reliable radio frequency micorelectromechanical switches. Jpn J Appl Phys 47(8):6558–6562CrossRefGoogle Scholar
  18. Osterberg P (1995) Electrostatically actuated microelectromechanical test structures for material property measurements. Ph.D. dissertation, MIT, Cambridge, MAGoogle Scholar
  19. Ouakad HM, Sedighi H, Younis MI (2017) One-to-one and three-to-one internal resonances in MEMS shallow arches. J Comput Nonlinear Dyn 12(5):051025CrossRefGoogle Scholar
  20. Patel CD, Rebeiz GM (2012) A high-reliability high-linearity highpower RF MEMS metal-contact switch for DC–40-GHz applications. IEEE Trans Microw Theory Tech 60(10):3096–3112CrossRefGoogle Scholar
  21. Patton S, Zabinski JS (2005) Fundamental studies of Au contacts in MEMS RF switches. Tribol Lett 18(2):215–230CrossRefGoogle Scholar
  22. Puers R, Lapadatu D (1996) Electrostatic forces and their effects on capacitive mechanical sensors. Sens Actuators A Phys 56(3):203–210CrossRefGoogle Scholar
  23. Rebeiz GM, Muldavin JB (2001) RF MEMS switches and switch circuits. IEEE Microw Mag 2(4):59–71CrossRefGoogle Scholar
  24. Rezazadeh G, Fathalilou M, Shabani R (2009a) Static and dynamic stabilities of a microbeam actuated by a piezoelectric voltage. Microsyst Technol 15:1785–1791CrossRefGoogle Scholar
  25. Rezazadeh G, Fathalilou M, Shabani R, Tarverdilou S, Talebian S (2009b) Dynamic characteristics and forced response of an electrostatically-actuated microbeam subjected to fluid loading. Microsyst Technol 15:1355–1363CrossRefGoogle Scholar
  26. Rezazadeh G, Fathalilou M, Sadeghi M (2011) Pull-in voltage of electrostatically-actuated microbeams in terms of lumped model pull-in voltage using novel design corrective coefficients. Sens Imaging 12:117–131CrossRefGoogle Scholar
  27. Vincent M, Rowe SW, Poulain C, Mariolle D, Chies L, Houzé F, Delamare J (2010) Field emission and material transfer in microswitches electrical contacts. AIP Lett 97(26):263503CrossRefGoogle Scholar
  28. Yang Z, Lichtenwalner D, Morris A, Krim J, Kingon AI (2010) Contact degradation in hot/cold operation of direct contact microswitches. J Micromech Microeng 20(10):105028CrossRefGoogle Scholar
  29. Yaralioglu G, Sanli Ergun A, Bayram B, Hæggstrom E, Khuri-Yakub BT (2003) Calculation and measurement of electromechanical coupling coefficient of capacitive micromachined ultrasonic transducers. IEEETrans Ultrason Ferroelectr Freq Control 50(4):449–456CrossRefGoogle Scholar
  30. Liu Y, Bey Y, Liu X (2016) Extension of the hot-switching reliability of RF-MEMS switches using a series contact protection technique. IEEE Trans Microw Theory Tech 64(10):3151–3162CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Mechanical Engineering DepartmentUrmia UniversityUrmiaIran
  2. 2.Department of EngineeringGerman University of Technology in OmanMuscatOman

Personalised recommendations