Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-23T13:34:39.609Z Has data issue: false hasContentIssue false
  • English
  • Français

Strength and fracture of Si micropillars: A new scanning electron microscopy-based micro-compression test

Published online by Cambridge University Press:  03 March 2011

B. Moser ,
K. Wasmer ,
L. Barbieri  and
J. Michler
B. Moser*
Affiliation:
EMPA Thun, Swiss Federal Institute for Materials Testing and Research, Laboratory for Materials Technology, 3602 Thun, Switzerland
K. Wasmer
Affiliation:
EMPA Thun, Swiss Federal Institute for Materials Testing and Research, Laboratory for Materials Technology, 3602 Thun, Switzerland
L. Barbieri
Affiliation:
Advanced Photonics Laboratory, Swiss Federal Institute of Technology EPFL, 1015 Lausanne, Switzerland
J. Michler
Affiliation:
EMPA Thun, Swiss Federal Institute for Materials Testing and Research, Laboratory for Materials Technology, 3602 Thun, Switzerland
*
a) Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

A novel method for in situ scanning electron microscope (SEM) micro-compression tests is presented. The direct SEM observation during the instrumented compression testing allows for very efficient positioning and assessment of the failure mechanism. Compression tests on micromachined Si pillars with volumes down to 2 μm3 are performed inside the SEM, and the results demonstrate the potential of the method. In situ observation shows that small diameter pillars tend to buckle while larger ones tend to crack before failure. Compressive strength increases with decreasing pillar diameter and reaches almost 9 GPa for submicrometer diameter pillars. This result is in agreement with earlier bending experiments on Si. Difficulties associated with precise strain measurements are discussed.

Keywords

Scanning electron microscopy (SEM)SiStrength
Type
Articles
Information
Journal of Materials Research , Volume 22 , Issue 4 , April 2007 , pp. 1004 - 1011
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Kraft, O. and Volkert, C.A.: Mechanical testing of thin films and small structures. Adv. Eng. Mater. 3, 99 (2001).3.0.CO;2-2>CrossRefGoogle Scholar
2Arzt, E.: Overview No. 130—Size effects in materials due to microstructural and dimensional contraints: A comparative review. Acta Mater. 46, 5611 (1998).CrossRefGoogle Scholar
3Ericson, F. and Schweitz, J.A.: Micromechanical fracture strength of silicon. J. Appl. Phys. 68, 5840 (1990).CrossRefGoogle Scholar
4Tsuchiya, T., Tabata, O., Sakata, J., and Taga, Y.: Specimen size effect on tensile strength of surface micromachined polycrystalline silicon thin films. J. Microeletromech. S 7, 106113(1998).CrossRefGoogle Scholar
5Sharpe, W.N. Jr., Yuan, B., Vaidyanathan, R., and Edwards, R.L.: Measurements of Young’s modulus, Poisson’s ratio, and tensile strength of polysilicon, in Tenth Annual International Workshop on Micro Electro Mechanical Systems (MEMS ’97 Proc., IEEE, 1997), pp. 424–429.CrossRefGoogle Scholar
6Jadaan, O.M., Nemeth, N.N., Bagdahn, J., and Sharpe, W.N.: Probabilistic Weibull behavior and mechanical properties of MEMS brittle materials. J. Mater. Sci. 38, 4087 (2003).CrossRefGoogle Scholar
7Greek, S., Ericson, F., Johansson, S., and Schweitz, J.A.: In situ tensile strength measurement and Weibull analysis of thick film and thin film micromachined polysilicon structures. Thin Solid Films 292, 247 (1997).CrossRefGoogle Scholar
8Namazu, T., Isono, Y., and Tanaka, T.: Evaluation of size effect on mechanical properties of single crystal silicon by nanoscale bending test using AFM. J. Microelectromech. Syst. 9, 450 (2000).CrossRefGoogle Scholar
9Weibull, W.: A Statistical Theory of the Strength of Materials, 151 (Generalstabens Litografiska Anstalts Förlag, Stockholm, 1939), pp. 1–4.Google Scholar
10Uchic, M.D., Dimiduk, D.M., Florando, J.N., and Nix, W.D.: Sample dimensions influence strength and crystal plasticity. Science 305, 986 (2004).CrossRefGoogle ScholarPubMed
11Dowling, N.E.: Mechanical Behavior of Materials Engineering Methods for Deformation, Fracture, and Fatigue, 2nd ed.Prentice Hall, Upper Saddle River, NJ, 1999).Google Scholar
12Hearn, E.J.: Mechanics of Materials an Introduction to the Mechanics of Elastic and Plastic Deformation of Solids and Structural Materials, 3rd ed. (Butterworth-Heinemann, Oxford, UK, 1999.Google Scholar
13Read, H.E. and Hegemier, G.A.: Strain softening of rock, soil, and concrete—A review article. Mech. Mater. 3, 271 (1984).CrossRefGoogle Scholar
14Drescher, A. and Vardoulakis, I.: Geometric softening in triaxial tests on granular material. Geotechnique 32, 291 (1982).CrossRefGoogle Scholar
15Vardoulakis, I., Labuz, J.F., Papamichos, E., and Tronvoll, J.: Continuum fracture mechanics of uniaxial compression on brittle materials. Int. J. Solids Struct. 35, 4313 (1998).CrossRefGoogle Scholar
16Hoek, E.: Brittle failure of rock, in Rock Mechanics in Engineering Practice, edited by Stagg, K.G. and Zienkiewicz, O.C. (Wiley, London, UK, 1968), 99–124.Google Scholar
17Namazu, T., Isono, Y., and Tanaka, T.: Nano-scale bending test of Si beam for MEMS, in Proceedings of the IEEE Thirteenth Annual International Conference on Micro Electro Mechanical Systems (IEEE, Miyazaki, Japan, 2000), pp. 205–210.Google Scholar
18Fitzgerald, A.M., Dauskardt, R.H., and Kenny, T.W.: Fracture toughness and crack growth phenomena of plasma-etched single crystal silicon. Sens. Actuators A Phys. 83, 194 (2000).CrossRefGoogle Scholar
19Ballarini, R., Muller, R.L., Yin, Y., Kahn, H., Stemmer, S., and Heuer, A.H.: Fracture toughness of polysilicon microdevices: A first report. J. Mater. Res. 12, 915 (1997).CrossRefGoogle Scholar
20Bhardwaj, J.K. and Ashraf, H.: Advanced silicon etching using high density plasmas, in Micromachining and Microfabrication Process Technology edited by Markus, K.W. (Proc. SPIE—Int. Soc. Opt. Eng., Austin, TX, 1995), pp. 224–233.CrossRefGoogle Scholar
21Rabe, R., Breguet, J-M., Schwaller, P., Stauss, S., Haug, F-J., Patscheider, J., and Michler, J.: Observation of fracture and plastic deformation during indentation and scratching inside the scanning electron microscope. Thin Solid Films 469–470, 206 (2004).CrossRefGoogle Scholar
22Zhang, H., Schuster, B.E., Wei, Q., and Ramesh, K.T.: The design of accurate micro-compression experiments. Scripta Mater. 54, 181 (2006).CrossRefGoogle Scholar