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Microsystem Technologies

, Volume 23, Issue 9, pp 3909–3925 | Cite as

CMOS-MEMS resonant pressure sensors: optimization and validation through comparative analysis

  • Saoni Banerji
  • Piotr Michalik
  • Daniel Fernández
  • Jordi Madrenas
  • Albert Mola
  • Josep Montanyà
Technical Paper

Abstract

An optimized CMOS-MEMS resonant pressure sensor with enhanced sensitivity at atmospheric pressure has been reported in this paper. The presented work reports modeling and characterization of a resonant pressure sensor, based on the variation of the quality factor with pressure. The relevant regimes of air flow have been determined by the Knudsen number, which is the ratio of the mean free path of the gas molecule to the characteristic length of the device. The sensitivity has been monitored for the resonator design from low vacuum to atmospheric levels of air pressure. This has been accomplished by reducing the characteristic length and optimization of other parameters for the device. While the existing analytical model has been adapted to simulate the squeeze film damping effectively and it is validated at higher values of air pressure, it fails to compute the structural damping mechanisms dominant in the molecular flow regime, i.e. at lower levels of air pressure. This discrepancy has been solved by finite element modeling that has incorporated both structural and film damping effects. The sensor has been designed with an optimal geometry of 140 × 140 × 8 µm having 6 × 6 perforations along the row and column of the plate, respectively, for maximum Q, with an effective mass of 0.4 µg. An enhanced quality factor of 60 and reduced damping coefficient of 4.34 µNs/m have been obtained for the reported device at atmospheric pressure. The sensitivity of the manufactured device is approximately −0.09 at atmospheric pressure and increases to −0.3 at 40 kPa i.e. in the lower pressures of slip flow regime. The experimental measurements of the manufactured resonant pressure sensor have been compared with that of the analytical and finite element modeling to validate the optimization procedure. The device has been manufactured using standard 250 nm CMOS technology followed by an in-house BEOL metal-layer release through wet etching.

Keywords

Perforation Resonant Frequency Quality Factor Flow Regime Knudsen Number 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

The authors would like to thank the anonymous reviewers for their valuable comments and suggestions to improve the quality of the paper. The work has been supported in part by the Spanish Ministry of Science and Innovation under project TEC2011-27047, and European Social Fund (ESF). Saoni Banerji holds an FI scholarship funding by the Catalan government and European Social Fund (ESF).

References

  1. Banerji S, Madrenas J, Fernandez D (2015, April 27–30) Optimization of parameters for CMOS MEMS resonant pressure sensors. Paper presented at 2015 Symposium on Design Test Integration and Packaging of MEMS and MOEMS (France), Montpellier (pp. 107–112)Google Scholar
  2. Bao M, Heng Y, Yuancheng S, Yuelin W (2003) Squeeze-film air damping of thick hole-plate. Sens Actuators A 108:212–217. doi: 10.1016/S0924-4247(03)00263-2 CrossRefGoogle Scholar
  3. Basu J, Bhattacharyya TK (2011) Micromechanical resonators for radio frequency communication applications. Microsyst Technol 17:1557–1580. doi: 10.1007/s00542-011-1332-9 CrossRefGoogle Scholar
  4. Brand O, Fedder GK, Hierold C, Korvink JG, Tabata O (2005) CMOS-MEMS. In: Timme HJ (ed) CMOS based pressure sensors, vol 2. Wiley-VCH Verlag GmbH, Weinheim, pp 257–335Google Scholar
  5. Brotz J (2004) Damping in CMOS-MEMS resonators. Master’s Project Report, Carnegie Mellon UniversityGoogle Scholar
  6. Chen WC, Fang W, Li SS (2011) A generalized CMOS-MEMS platform for micromechanical resonators monolithically integrated with circuits. J Micromech Microeng 21(065012):15. doi: 10.1088/0960-1317/21/6/065012 Google Scholar
  7. COMSOL Multiphysics (2008) MEMS Module. https://extras.csc.fi/math/comsol/3.5/doc/mems/memsmodlib.pdf. Accessed 10 Dec 2014
  8. Darling RB, Hivick C, Jianyang X (1998) Compact analytical modeling of squeeze film damping with arbitrary venting conditions using a Green’s function approach. Sens Actuators A 70:32–41. doi: 10.1016/S0924-4247(98)00109-5 CrossRefGoogle Scholar
  9. Fernández D, Ricart J, Madrenas J (2010) Experiments on the release of CMOS-Micromachined metal layers. J Sens 2010:7. doi: 10.1155/2010/937301 CrossRefGoogle Scholar
  10. Kaajakari (2009) Practical MEMS. Small gear Publishing, Las VegasGoogle Scholar
  11. Khine L (2010) Performance parameters of micromechanical resonators. Ph.D. dissertation, National University of SingaporeGoogle Scholar
  12. Kim E, Cho Y, Kim M (1999) Effect of holes and edges on the squeeze film damping of perforated micromechanical structures 12th IEEE Intern. Conference on MEMS (MEMS’99), Orlando, FL, January 17–21, pp 296–301Google Scholar
  13. Michalik P, Sánchez-Chiva JM, Fernández D, Madrenas J (2015) CMOS BEOL-embedded z-axis accelerometer. Electron Lett 51(11):865–867CrossRefGoogle Scholar
  14. Pandey AK, Pratap R (2007) A comparative study of analytical squeeze film damping models in rigid rectangular perforated MEMS structures with experimental results Microfluidics Nanofluidics 4:205–218. doi: 10.1007/s10404-007-0165-4 Google Scholar
  15. Pandey AK, Pratap R, Chau FS (2006) Analytical solution of the modified Reynolds equation for squeeze film damping in perforated MEMS structures. Sens Actuators A 135:839–848. doi: 10.1016/j.sna.2006.09.006 CrossRefGoogle Scholar
  16. Pandey AK, Pratap R, Chau FS (2008) Effect of pressure on fluid damping in MEMS torsional resonators with flow ranging from continuum to molecular regime. Exp Mech 48:91–106. doi: 10.1007/s11340-007-9076-2 CrossRefGoogle Scholar
  17. Rawat U, Pasula VV, Nair DR, Dasgupta A (2013) Efficient anchor design for quality factor enhancement in a silicon nitride-on-siliconlateral bulk mode resonator. http://www.comsol.es/paper/download/182757/rawat_presentation.pdf. Accessed 18 Sep 2015
  18. Senturia SD (2001) Microsystem design. Kluwer Academic Publishers Norwell, MAGoogle Scholar
  19. Škvor Z (1967) On acoustical resistance due to viscous losses in the air gap of electrostatic transducers. Acustica 19:295–297Google Scholar
  20. Veijola T (2006) Analytic damping model of an MEM perforation cell. Microfluid Nanofluid 2(3):249–260. doi: 10.1007/s10404-005-0072-5 CrossRefGoogle Scholar
  21. Vermuri S (2000) Behavioral modeling of viscous damping in MEMS. M.S. Thesis Report, Carnegie Mellon UniversityGoogle Scholar
  22. Yinan L, Junbo W, Zhenyu L, Deyong C, Jian C (2015) A resonant pressure microsensor capable of self-temperature compensation. Sensors 15:10048–10058. doi: 10.3390/s150510048 CrossRefGoogle Scholar
  23. Younis MI (2011) MEMS Linear and Nonlinear Statics and Dynamics. New York, USAGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Saoni Banerji
    • 1
  • Piotr Michalik
    • 1
  • Daniel Fernández
    • 2
  • Jordi Madrenas
    • 1
  • Albert Mola
    • 3
  • Josep Montanyà
    • 2
  1. 1.Electronic Engineering DepartmentUniversitat Politècnica de CatalunyaBarcelonaSpain
  2. 2.Nanusens, CENT—Parc Tecnològic del VallèsCerdanyola Del VallèsSpain
  3. 3.InContext ABStockholmSweden

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