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Measurement of Residual Stress-Induced Bending Moment of P+ Silicon Films

Published online by Cambridge University Press:  22 February 2011

W. H. Chu
Affiliation:
Department of Electrical Engineering and Applied Physics, Case Western Reserve University, Cleveland, Ohio 44106, U.S.A.
M. Mehregany
Affiliation:
Department of Electrical Engineering and Applied Physics, Case Western Reserve University, Cleveland, Ohio 44106, U.S.A.
X. Ning
Affiliation:
Department of Materials Science and Engineering, Case Western Reserve University, Cleveland, Ohio 44106, U.S.A.
P. Pirouz
Affiliation:
Department of Materials Science and Engineering, Case Western Reserve University, Cleveland, Ohio 44106, U.S.A.
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Abstract

This paper presents results from measurements of residual stress-induced bending moment of heavily-boron-doped (p+) silicon films. Microfabricated free-standing cantilever beams of p+ silicon were fabricated by using anisotropie etching of (100) silicon wafers in ethylene-diamine and pyrocatechol. The p+ etch stops forming the cantilevers were created by diffusion from a solid source at 1125°C for one and two hour time durations. The nonuniform residual stress distribution through the thickness of the p+ silicon cantilevers resulted in a deflection of the beams. The as-diffused p+ silicon films had a residual stress distribution through the film thickness which resulted in negative bending moments. Thermal oxidation subsequent to the diffusion step modified the residual stresses near the top surface or, perhaps, plastically deformed the near surface region of the p+ thin film. As a result, thermally oxidized p+ silicon films exhibited a positive bending moment. Measurements of the deflection curves of the beams in conjunction with beam theory were used to calculate the residual stress-induced bending moments.

Type
Research Article
Copyright
Copyright © Materials Research Society 1992

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References

[1] Ding, X., Mechanical properties of silicon films and capacitive microsensors, Ph. D Thesis, Case Western Reserve University, Cleveland, Ohio, May 1990 Google Scholar
[2] Ding, X., Ko, W. H., and Mansour, J. M., Sensors and Actuators, A21–A23, 886 (1990)Google Scholar
[3] Smirnov, I. N., Sov. Phys. Solid State, 20, 224 (1975)Google Scholar
[4] Milevsku, L. S. and Chuvilin, Yu. N., Sov. Phys. Solid State, 22, 1536 (1980)Google Scholar
[5] Huff, M. A., Senturia, S. D., Howe, R. T., in Proceedings, IEEE Solid-State Sensor and Actuator Workshop, Hilton Head, SC, 47 (1988)Google Scholar
[6] Maseeh, F. and Senturia, S. D., Sensors and Actuators, A21–A23, 861 (1990)Google Scholar
[7] Ning, X. J., Pirouz, P., Mehregangy, M., and Chu, W. H., Technical Digest, 6th Int. Coni, on Solid-State Sensors and Actuators, San Francisco, CA, 755 (1991)Google Scholar
[8] Timoshenko, S. P., Theory of plates and shells, 1st ed. (McGraw-Hill Book company, Inc. New York, 1940), p. 41 Google Scholar
[9] Gere, J. M. and Timoshenko, S. P., Mechanics of materials, 2nd ed. (PWS Publishers, Boston, MA) p. 207 Google Scholar
[10] Jaccodine, R. T. and Schlegel, W. A., J. Appi Phys., 37, 2429 (1966)Google Scholar