Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-28T12:21:50.242Z Has data issue: false hasContentIssue false
  • English
  • Français

Mechanical Properties and Reliability of Amorphous vs. Polycrystalline Silicon Thin Films

Published online by Cambridge University Press:  01 February 2011

Joao Gaspar ,
Oliver Paul ,
Virginia Chu  and
Joao Pedro Conde
Joao Gaspar
Affiliation:
[email protected], University of Freiburg, Department of Microsystems Engineering (IMTEK), Microsystems Materials Laboratory, Georges-Koehler-Allee 103, Freiburg, 79110, Germany, +497612037194, +497612037192
Oliver Paul
Affiliation:
[email protected], University of Freiburg, Dept. Microsystems Eng. (IMTEK), Freiburg, 79110, Germany
Virginia Chu
Affiliation:
[email protected], INESC Microsistemas e Nanotecnologias, Lisbon, 1000-029, Portugal
Joao Pedro Conde
Affiliation:
[email protected], INESC Microsistemas e Nanotecnologias, Lisbon, 1000-029, Portugal
Get access

Abstract

This paper presents the mechanical characterization of both elastic and fracture properties of thin silicon films from the load-deflection response of membranes, also known as the bulge test. Properties extracted include the plane-strain modulus, prestress, fracture strength and Weibull modulus. Diaphragms made of low-temperature, hydrogenated amorphous and nanocrystalline silicon films (a-Si:H and nc-Si:H, respectively) deposited by plasma enhanced chemical vapor deposition (PECVD) and, for comparison, membranes composed of high-temperature polycrystalline silicon (poly-Si) deposited by low pressure chemical vapor deposition (LPCVD) have been fabricated and characterized. The structures are bulged until failure occurs. From the stress profiles in the diaphragms at fracture, the brittle material strength is analyzed using Weibull statistics. The bulge setup is fully automated for the sequential measurement of several membranes on a substrate realizing the high-throughput acquisition of data under well controlled conditions. A comprehensive study of the mechanical properties of low-temperature silicon films as a function of deposition parameters, namely substrate temperature, RF power, hydrogen dilution and doping, is presented.

Keywords

thin filmmicroelectro-mechanical (MEMS)elastic properties
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1066: Symposium A – Amorphous and Polycrystalline Thin-Film Silicon Science and Technology—2008 , 2008 , 1066-A15-04
Copyright
Copyright © Materials Research Society 2008

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

1. Judy, Jack W. Smart Mater. Struct. 10, 1115 (2001).Google Scholar
2. Maluf, N. An Introduction to MEMS Engineering, Artech House, Boston, 2000.Google Scholar
3. Gaspar, J. Chu, V. Conde, J. P. J. Appl. Phys. 93, 10018 (2003).Google Scholar
4. Gaspar, J. Chu, V. Louro, N. Cabeça, R., Conde, J.P. J. Non-Cryst. Sol., 299-302, 1224 (2002).Google Scholar
5. Gaspar, J. Chu, V. Conde, J. P. 17th IEEE MEMS 2004 Conf. Tech. Dig., 633 (2004).Google Scholar
6. Syllaios, A. J. Schimert, T. R. Gooch, R. W. McCarde, W. L. Ritchey, B. A. Tregilgas, J. H. Mat. Res. Soc. Symp. Proc. 609, A14.4.1 (2000).Google Scholar
7. Bromley, E. I. Randall, J. Flanders, D. Mountain, R. J. Vac. Sci. Technol. B 1, 1364 (1983).Google Scholar
8. Ziebart, V. Paul, O. Münch, U., Schwizer, J. Baltes, H. J. Microelectrom. Syst. 7, 320 (1998).Google Scholar
9. Paul, O. and Ruther, P. Material Characterization, Ch. 2 in CMOS . MEMS, Advanced Micro & Nanosystems Series, Eds. Brand, O. Fedder, G. K., Wiley-VCH, Weinheim, 2005.Google Scholar
10. Gaspar, J. Schmidt, M. Held, J. Paul, O. Mat. Res. Soc. Symp. Proc. 1052, DD1.2 (2008).Google Scholar
11. Paul, O. and Gaspar, J.; Thin-Film Characterization Using the Bulge Test, Ch. 3 in Reliability of MEMS, Eds. Tabata, O. Tsuchiya, T. Wiley-VCH, Weinheim, 2007.Google Scholar
12. Alpuim, P. Chu, V. Conde, J. P. J. Appl. Phys. 86, 3812 (1999).Google Scholar