A new MEMS based variable capacitor using electrostatic vertical comb drive actuator and auxiliary cantilever beams

  • Saeid AfrangEmail author
  • Nooshin Nematkhah
Technical Paper


We have proposed a new wide tunable MEMS variable capacitor. In the proposed structure, an electrostatic vertical comb drive actuator is used to extend the tuning range. Moreover, the auxiliary cantilever-beams are used in the electrostatic comb drive actuator to delay the front sticking (Pull in) and increase the tunability. The effect of lateral gap distance between the fingers in the capacitance tunability is investigated. Not only a full review of electrostatic actuator portion is done but also the electric fields related to lateral gap changes are simulated by COMSOL software and its results are compared with theoretical results as well. The structure is calculated using MATLAB software. To verify, the calculated results are compared with simulated results using Intellisuite software. According to calculation and simulation results the achieved tuning range is 285%.



  1. Afrang S, Rezazadeh Gh, Mobki H (2015) A new MEMS based variable capacitor with wide tunabilit, high linearity and low actuation voltage. J Microelectron 46(2):191–197CrossRefGoogle Scholar
  2. Azizi A, Malekzadeh N, Mobki H, Arbi A (2018) Bifurcation behaviour and stability analysis of a nano-beam subjected to electrostatic pressure. Appl Comput Math 7(1–2):1–11Google Scholar
  3. Bakri-Kassem M, Mansour R (2004) An improved design for parallel plate mems variable capacitors. In: Microwave symposium digest, IEEE MTT-S international, 2:865–868Google Scholar
  4. Bakri-Kassem M, Mansour R (2004b) Two movable-plate nitride-loaded mems variable capacitor. Microwave theory and techniques. IEEE Trans 52(3):831–837Google Scholar
  5. Bakri-Kassem M, Mansour R (2006) High tuning range parallel plate mems variable capacitors with arrays of supporting beams. In: Micro electro mechanical systems, MEMS Istanbul. 19th IEEE international conference on, pp 666–669Google Scholar
  6. Borwick I, Stupar P, DeNatale J, Anderson R, Erlandson R (2003) Variable mems capacitors implemented into RF filter systems. Microwave theory and techniques. IEEE Trans 51(1):315–319Google Scholar
  7. Bryzek J, Abbott E, Flannery A, Cagle D, Maitan J (2003) Control issues for MEMS. In: Proceedings of the 42nd IEEE conference on decision and control, vol 3, pp 3039–3047. 9–12 Dec 2003Google Scholar
  8. Chen C, Lee C (2004) Design and modeling for comb drive actuator with enlarged static displacement. Sens Actuators 115(2–3):530–539CrossRefGoogle Scholar
  9. Dec A, Suyama K (2000) Micromachined electro-mechanically tunable capacitors and their applications for RF IC’s. IEEE J Solid State Circ 35(8):1231–1237CrossRefGoogle Scholar
  10. Elata D, Bochobza-Degani O, Nemirovsky Y (2003) Analytical approach and numerical alpha-lines method for pull-in hyper-surface extraction of electrostatic actuators with multiple uncoupled voltage sources. J Microelectromech Syst 53:681–691CrossRefGoogle Scholar
  11. Faheem F, Hoivik N, Lee Y, Gupta K (2003) Post-enabled precision flip-chip assembly for variable mems capacitor. In: Microwave symposium digest, 2003 IEEE MTT-S International, 3:1927–1930Google Scholar
  12. Jaecklin VP, Linder C, De Rooij N F, Moret JM (1992) Micromechanical comb actuators with low driving voltage. J Micromech Microeng 2:250–255CrossRefGoogle Scholar
  13. Legtenberg R, Groeneveld A, Elwenspoek M (1996) Comb-drive actuators for large displacements. J Micromech Microeng 53:320–329CrossRefGoogle Scholar
  14. Li Z, Tien NC (2002) A high tuning-ratio silicon micromachined variable capacitor with low driving voltage. Solid State Sens Actuat Microsyst 13(3):239–242Google Scholar
  15. Mobki H, Sadeghi M, Afrang S, Rezazadeh G (2011) On tenability of a MEMS based variable capacitor with a novel structure. Microsyst Technol 17:1447–1452CrossRefGoogle Scholar
  16. Nguyen C, Katehi L, Rebeiz G (1998) Micromachined devices for wireless communications. IEEE 86(8):1756–1768CrossRefGoogle Scholar
  17. Nguyen H, Hah D, Patterson P, Wu M (2002) A novel MEMS tunable capacitor based on angular vertical comb drive actuators. Solid-state sensor, actuator and microsystems 13(3):277–280Google Scholar
  18. Nguyen H, Hah D, Patterson P, Chao R, Piyawattanametha W, Lau E, Wu M (2004) Angular vertical comb-driven tunable capacitor with high-tuning capabilities. Microelectromech Syst J 13(3):406–413CrossRefGoogle Scholar
  19. Peroulis D, Katehi L (2003) Electrostatically-tunable analog RF MEMS varactors with measured capacitance range of 300%. In: Microwave Symposium Digest, 2003 IEEE MTT-S International, 3(8–13):1793–1796Google Scholar
  20. Rijks T, Beek J, Steeneken P, Ulenaers M, De Coster J, Puers R (2004) RF MEMS tunable capacitors with large tuning ratio. In: MicroElectro mechanical systems, 17th IEEE International Conference on. (MEMS), pp 777–780Google Scholar
  21. Roack R, Young W (1975) Formulas for stress and strain. McGraw Hill, New YorkGoogle Scholar
  22. Yao J, Park S, Anderson R, DeNatale J (1998) High tuning ratio MEMS-based tunable capacitors for RF communications. Solid-state Sensor and Actuator Workshop, Hilton Head Island, pp 124–127Google Scholar
  23. Yao J, Park S, DeNatale J (2000) A low power/low voltage electrostatic actuator for RF MEMS applications. Proceedings of Solid-state Sensor and Actuator Workshop, Hilton Head Island, pp 246–249Google Scholar
  24. Young D, Boser B (1996) A micromachined variable capacitor for monolithic low-noise VCOs. In: Proceedings of IEEE solid-state sensors actuators workshop, Hilton Head, SC, pp 86–89Google Scholar
  25. Young D, Tham J, Boser B (1999) A micromachine-based low phase-noise GHz voltage-controlled oscillator for Wireless communications. In: The 10th international conference on solid-state sensors and actuators (Transducers’99), Sendai, Japan, 19, 11(5):285–300Google Scholar
  26. Zhu Y, Yuce MR, Moheimani (2010) A low loss MEMS tunable capacitor with movable dielectric. In: IEEE sensors 2009 conference, pp 651–654Google Scholar
  27. Zou J, Liu C, Aline J, Chen J, Kang S (2000) Development of a wide tuning range MEMS tunable capacitor for wireless communication systems. In: IEEE IEDM, pp 403–406Google Scholar

Copyright information

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

Authors and Affiliations

  1. 1.Department of Electrical EngineeringUrmia UniversityUrmiaIran

Personalised recommendations