SciELO - Scientific Electronic Library Online

vol.55 issue1Resolved component of the photon in heavy quark photoproductionOptimization of the diffraction efficiency in non-uniform gratings in sillenite crystals (Bi12SiO20 and Bi12TiO2) considering the variation of fringe period, optical activity and polarization angles in a strong non-linear regime author indexsubject indexsearch form
Home Pagealphabetic serial listing  

Services on Demand




Related links

  • Have no similar articlesSimilars in SciELO


Revista mexicana de física

Print version ISSN 0035-001X

Rev. mex. fis. vol.55 n.1 México Feb. 2009




Electromechanical analysis of a piezoresistive pressure microsensor for low–pressure biomedical applications


A.L. Herrera–Maya , d, B.S. Soto–Cruzb, F. López–Huertac, and L.A. Aguilera Cortésd


ª Centro de Investigación en Micro y Nanotecnología, Universidad Veracruzana, Boca del Río, Ver, México.

b Centro de Investigación en Dispositivos Semiconductores, Benemérita Universidad Autónoma de Puebla, Puebla, Pue., México.

c Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Puebla, Pue., México.

d Departamento Ingeniería Mecánica, Campus Irapuato–Salamanca, Universidad de Guanajuato, Salamanca, Gto. México.


Recibido el 9 de junio de 2008
Aceptado el 12 de enero de 2009



The electromechanical analysis of a piezoresistive pressure microsensor with a square–shaped diaphragm for low–pressure biomedical applications is presented. This analysis is developed through a novel polynomial model and a finite element method (FEM) model. A microsensor with a diaphragm 1000 µm length and with three different thicknesses (10, 15, and 20 µm) is studied. The electric response of this microsensor is obtained with a Wheatstone bridge of four p–type piezoresistors located on the diaphragm surface. The diaphragm that is 10 µm thick exhibits a maximum deflection of 3.74 µm using the polynomial model, which has a relative difference of 5.14 and 0.92% with respect to the Timoshenko model and the FEM model, respectively. The maximum sensitivity and normal stress calculated using the polynomial model are 1.64 mV/V/kPa and 102.1 MPa, respectively. The results of the polynomial model agree well with the Timoshenko model and FEM model for small deflections. In addition, the polynomial model can be easily used to predict the deflection, normal stress, electric response and sensitivity of a piezoresistive pressure microsensor with a square–shaped diaphragm under small deflections.

Keywords: Finite element model; piezoresistors; polynomial model; pressure microsensor.



El analisis electromecánico de un microsensor de presión piezoresistivo con un diafragma de sección cuadrada para aplicaciones biomédicas de baja presión es presentado. Este análisis es desarrollado mediante un nuevo modelo polinomial y un modelo con el método elemento finito (FEM). Un microsensor con un diafragma de 1000 µm de longitud y tres diferentes espesores (10, 15 y 20 µm) es estudiado. La respuesta electrica de éste microsensor es obtenida mediante un puente de Wheatstone con cuatro piezoresistores tipo p localizados sobre la superficie del diafragma. El diafragma con 10 µm de espesor presenta una deflexion máxima de 3.74 µm utilizando el modelo polinomial, el cual tiene una diferencia relativa de 5.14 and 0.92% con respecto al modelo de Timoshenko y al modelo FEM, respectivamente. La máxima sensibilidad y esfuerzo normal calculado con el modelo polinomial son 1.64 mV/V/kPa and 102.1 MPa, respectivamente. Los resultados del modelo polinomial concuerdan bien con el modelo de Timoshenko y el modelo FEM para pequeñas deflexiones. Además, el modelo polinomial puede ser utilizado fácilmente para predecir la deflexión, esfuerzo normal, respuesta eléctrica y sensibilidad de un microsensor de presión piezoresistivo con un diafragma de sección cuadrada sujeto a pequeñas deflexiones.

Descriptores: Modelo de elemento finito; piezoresistores; modelo polinomial; microsensor de presión.


PACS: 07.10.Cm;07.07.Df;47.11.Fg





This work was supported by the University of Guanajuato (UG DINPO project 099/2008) and CONACYT through project 84605. We would also like to thank Prof. Jerry Hemmye of Western Michigan University for useful discussions and suggestions.



1. C. Pramanik, H. Saha, and U. Gangopadhyay, J. Micromech. Microeng. 16 (2006) 2060.        [ Links ]

2. S. Marco, J. Samitier, O. Ruiz, J.R. Morante, and J.E. Steve, Meas. Sci. Technol. 7 (1996) 1195.        [ Links ]

3. B.H. Bae, et al., J. Micromech. Microeng. 13 (2003) 613.        [ Links ]

4. G.H. Mohamed, MEMS Handbook (Boca Raton, FL: CRC Press, 2002).        [ Links ]

5. R. Schlierf, et al., J. Micromech. Microeng. 17 (2007) S98.        [ Links ]

6. A.V. Chavan and K.D. Wise, J. Microelectromech. Syst. 10 (2001) 580.        [ Links ]

7. Z. Yan–Hong, et al., IEEE Sensors J. 7 (2007) 1742.        [ Links ]

8. J.K. Otto, T.D. Brown, and J.J. Callaghan, Exp. Mech. 39 (1999) 317.        [ Links ]

9. G. Bistué, et al., J. Micromech. Microeng. 7 (1997) 244.        [ Links ]

10. J. Jordana and A.R. Pallàs–Areny, Sens. Actuators A 127 (2006) 69.        [ Links ]

11. Y. Kanda and A Yasukawa, Sens. Actuators A 62 (1997) 539.        [ Links ]

12. T. Lisec, M. Kreutzer, and B. Wagner, IEEE Trans. Electron Dev. 43 (1996) 1447.        [ Links ]

13. S. Beeby, G. Ensell, M. Kraft, and N. White, MEMS Mechanical sensors (Norwood, MA: Artech House, 2004).        [ Links ]

14. H.P. Le, K. Shah, J. Singh, and A. Zayegh, AnalogIntegr. Circ. Sig Process. 48 (2006) 21.        [ Links ]

15. N. Maluf, An Introduction to Microelectromechanical Systems Engineering 2nd ed. (Norwood, MA: Artech House, 2004).        [ Links ]

16. L. Lin and W. Yung, Mechatronics 8 (1998) 505.        [ Links ]

17. L. Lin, H.C. Chu, and Y.W. Lu, J. Microelectromech. Syst. 8 (1999) 514.        [ Links ]

18. G. Bistué, et al., Sens. Actuators A 62 (1997) 591.        [ Links ]

19. C. Gin–Shin, J. Ming–Shaung, and F. Yean–Kuen, Sens. Actuators A 86 (2000) 108.        [ Links ]

20. A.C. Ugural, Stresses in Plates and Shells (New York: McGraw Hill, 1981).        [ Links ]

21. E. Ventsel and T. Krauthammer, Thin Plates and Shells: Theory, Analysis, and Applications (New York: CRC Press, 2001).        [ Links ]

22. R. Szilard, Theories and Applications of Plate Analysis: Classical, Numerical and Engineering Methods (New Jersey: John Wiley & Sons, 2004).        [ Links ]

23. S.P. Timoshenko and S. Woinowsky–Krieger, Theory of Plates and Shells (New York: McGraw–Hill, 1959).        [ Links ]

24. S.K. Clark and K.D. Wise, IEEE Trans. Electron Dev. 26 (1979) 1887.        [ Links ]

25. T. Toriyama and S. Sugiyama, J. Microelectromech. Syst. 11 (2002) 598.        [ Links ]

26. J.M. Borky, Silicon Diaphragm Pressure Sensors with Integrated Electronics, (Ph. D. Thesis, University of Michigan, Ann Arbor, 1997).        [ Links ]

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License