Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-03T05:17:26.026Z Has data issue: false hasContentIssue false
  • English
  • Français

Residual Stresses in MEMS Structures

Published online by Cambridge University Press:  10 February 2011

B. S. Majumdar ,
W. D. Cowan  and
N. J. Pagano
B. S. Majumdar
Affiliation:
Department of Materials Science, New Mexico Tech, Socorro, NM 87801
W. D. Cowan
Affiliation:
Materials Directorate, Air Force Research Laboratory, Wright Patterson AFB, Ohio 45433
N. J. Pagano
Affiliation:
Materials Directorate, Air Force Research Laboratory, Wright Patterson AFB, Ohio 45433
Get access

Abstract

The magnitude and origin of residual stresses in thin polysilicon MEMS structures are discussed in this article. The curvature of polysilicon beams were determined at different temperatures. An accurate method of analysis that avoids the thick substrate approximation is described. The polysilicon beams without an Au layer exhibited temperature-independent curvatures, indicating that their residual stresses were largely process related. Beams with an Au top-coat exhibited a strong temperaturedependent effect, and allowed derivation of a stress-free temperature of 143°C. The technique allowed an independent estimate of the thermal expansion coefficient of polysilicon, namely 2.5×10−6 to 3.1×10−6/°C.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 594: Symposium V – Thin Films - Stresses & Mechanical Properties VIII , 1999 , 231
Copyright
Copyright © Materials Research Society 2000

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 Roggemann, M.C., Bright, V.M., Welsh, B.M., Hicke, S.R., Roberts, P.C., Cowan, W.D., and Comtois, J.H., Opt. Engg., Vol. 36, No.5, pp.1326–1338 (1997)Google Scholar
2. Thornton, J.A. and Hoffman, D.W., Thin Solid Films, Vol. 171, pp.5–31 (1989)Google Scholar
3. Cowan, W.D., Bright, V.M., Alvin, A.A., and Koester, D.A., SPIE Microlithography and Metrology in Micromachining III, Vol. 3525, pp.56–67 (1998)Google Scholar
4. Timoshenko, S., J. Opt. Soc. Am., Vol. 11, pp.233–255 (1925)Google Scholar
5. d'Huerle, F.M. and Harper, J.M.E., Thin Solid Films, Vol. 171, pp.81–92 (1989)Google Scholar
6. Stoney, G.G., Proc. Roy Soc., Vol. 9, pp.172–175 (1909)Google Scholar