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Wafer-Level Strength and Fracture Toughness Testing of Surface-Micromachined MEMS Devices

Published online by Cambridge University Press:  10 February 2011

H. Kahn ,
N. Tayebi ,
R. Ballarini ,
R.L. Mullen  and
A.H. Heuer
H. Kahn
Affiliation:
Department of Materials Science and Engineering, Case Western Reserve University, Cleveland, Ohio
N. Tayebi
Affiliation:
Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, Ohio
R. Ballarini
Affiliation:
Department of Civil Enginering, Case Western Reserve University, Cleveland, Ohio
R.L. Mullen
Affiliation:
Department of Civil Enginering, Case Western Reserve University, Cleveland, Ohio
A.H. Heuer
Affiliation:
Department of Materials Science and Engineering, Case Western Reserve University, Cleveland, Ohio
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Abstract

Determination of the mechanical properties of MEMS (microelectromechanical systems) materials is necessary for accurate device design and reliability prediction. This is most unambiguously performed using MEMS-fabricated test specimens and MEMS loading devices. We describe here a wafer-level technique for measuring the bend strength, fracture toughness, and tensile strength of MEMS materials. The bend strengths of surface-micromachined polysilicon, amorphous silicon, and polycrystalline 3C SiC are 5.1±1.0, 10.1±2.0, and 9.0±1.0 GPa, respectively. The fracture toughness of undoped and P-doped polysilicon is 1.2±0.2 MPa√m, and the tensile strength of polycrystalline 3C SiC is 3.2±1.2 GPa. These results include the first report of the mechanical strength of micromachined polycrystalline 3C SiC.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 605: Symposium MM – Materials Science of Microelectromechanical Systems Devices II , 1999 , 25
Copyright
Copyright © Materials Research Society 2000

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References

1. Greek, S., Ericson, F., Johansson, S., Furtsch, M., and Rump, A., “Mechanical characterization of thick polysilicon films: Young's modulus and fracture strength evaluated with microstructures,” J. Micromech. Microeng., 9, pp. 245–251 (1999).Google Scholar
2. Tsuchiya, T., Tabata, O., Sakata, J., and Taga, Y., “Specimen size effect on tensile strength of surface-micromachined polycrystalline silicon thin films,” J. Microelectromech. Syst., 7, pp. 106–113 (1998).10.1109/84.661392Google Scholar
3. Biebl, M. and Philipsborn, H. von, “Fracture strength of doped and undoped polysilicon,” Proc. of the 8th Intl. Conf. on Solid-State Sensors and Actuators, Transducers 95, pp. 72–75 (1995).Google Scholar
4. Koskinen, J., Steinwall, J.E., Soave, R., and Johnson, H.H., “Microtensile testing of free-standing polysilicon fibers of various grain sizes,” J. Micromech. Microeng., 3, pp. 13–17 (1993).Google Scholar
5. Sharpe, W.N., Turner, K.T., and Edwards, R.L., “Tensile testing of polysilicon,” Experimental Mech., 39, pp. 162–170 (1999).Google Scholar
6. Tsuchiya, T., Sakata, J., and Taga, Y., “Tensile strength and fracture toughness of surface micromachined polycrystalline silicon thin films prepared under various conditions,” in Thin-films: stresses and mechanical properties VII, ed. by Cammarata, R.C., Natasi, M., Busso, E.P., and Oliver, W.C. (Mater. Res. Soc. Proc. 505, Pittsburgh, PA 1998), pp. 285–290.Google Scholar
7. Sharpe, W.N., Brown, S., Jonhson, G.C., and Knauss, W., “Round-robin tests of modulus and strength of polysilicon,” in Microelectromechanical Structures for Materials Research, ed. by Brown, S., Gilbert, J., Guckel, H., Howe, R., Johnson, G., Krulevitch, P., and Muhlstein, C. (Mater. Res. Soc. Proc. 518, Pittsburgh, PA 1998), pp. 57–65.Google Scholar
8. Sharpe, W.N., Yuan, B., and Edwards, R.L., “Fracture tests of polysilicon film,” in Thin-films: stresses and mechanical properties VII, ed. by Cammarata, R.C., Natasi, M., Busso, E.P., and Oliver, W.C. (Mater. Res. Soc. Proc. 505, Pittsburgh, PA 1998), pp. 51–56.Google Scholar
9. Arsdell, W.W. Van and Brown, S.B., “Subcritical crack growth in silicon MEMS,” J. Microelecromech. Syst., 8, pp. 319–327 (1999).Google Scholar
10. Du, Y., Chang, X., Shi, N., Chung, J.C.Y., and Rao, K.P., “A strength evaluation of SiC fibers prepared by RFCVD,” JOM, 50, pp. 36–39 (1998).Google Scholar
11. Bhatt, R.T. and Hull, D.R., “Strength-degrading mechanisms for chemically-vapor-deposited SCS-6 silicon carbide fibers in an argon environment,” J. Am. Ceram. Soc., 81, pp. 957–964 (1998).Google Scholar
12. Ohji, T., Yamauchi, Y., Kanematsu, W., and Ito, S., “Tensile rupture strength and fracture defects of sintered silicon carbide,” J. Am. Ceram. Soc., 72, pp. 688–690 (1989).Google Scholar
13. Yavuz, B.O. and Tressler, R.E., “Threshold stress intensity for crack growth in silicon carbide ceramics,” J. Am. Ceram. Soc., 76, pp. 1017–1024 (1993).10.1111/j.1151-2916.1993.tb05329.xGoogle Scholar
14. Kodama, H. and Miyoshi, T., “Study of fracture behavior of very fine-grained silicon carbide ceramics,” J. Am. Ceram. Soc., 73, pp. 3081–3086 (1990).10.1111/j.1151-2916.1990.tb06720.xGoogle Scholar
15. Petrovic, J.J. and Roof, R.B., “Fracture toughness of a beta-SiC whisker,” J. Am. Ceram. Soc., 67, pp. C219–C220 (1984).Google Scholar
16. Kahn, H., Ballarini, R., Mullen, R.L., and Heuer, A.H., “Electrostatically actuated failure of microfabricated polysilicon fracture mechanics specimens,” Proc. R. Soc. Lond. A, 455, pp. 3807–3823 (1999).Google Scholar
17. Kahn, H., Tayebi, N., Ballarini, R., Mullen, R.L., and Heuer, A.H., “Fracture toughness of polysilicon MEMS devices,” to appear in Sensors and Actuators A.Google Scholar
18. Yasseen, A.A., Zorman, C.A., and Mehregany, M., “Surface micromachining of polycrystalline SiC films using microfabricated molds of SiO2 and polysilicon,” J. Microelectromech. Syst., 8, pp. 237–242 (1999).10.1109/84.788626Google Scholar
19. Keller, C., Microfabricated High Aspect Ratio Silicon Flexures (MEMS Precision Instruments, El Cerrito, CA 1998), pp 185–202.Google Scholar
20. Cook, R.F. and Pharr, G.M., “Direct observation and analysis of indentation cracking in glasses and ceramics,” J. Am. Ceram. Soc., 73, pp. 787–817 (1990).Google Scholar