Hostname: page-component-5c6d5d7d68-xq9c7 Total loading time: 0 Render date: 2024-08-20T13:16:45.215Z Has data issue: false hasContentIssue false

Elastic flexure of bilayered beams subject to strain differentials

Published online by Cambridge University Press:  31 January 2011

T-J. Chuang
Affiliation:
Ceramics Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899–8521
S. Lee
Affiliation:
Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan 30043
Get access

Abstract

The residual stresses present in a thin film and the curvature formed at its substrate during deposition have been a great concern to electrochemists and process engineers. Here a new hybrid analytical method is presented to reanalyze the flexural problem subjected to a strain differential in the general case. It was shown that the present solutions for ultrathin films agree with Stoney's equation. Moreover, single or dual neutral axes resulted, depending on materials and thickness ratios between the film and the substrate. Quantitative differences with others in the solutions of deformed curvature and residual stress are discussed in a representative case of GaAs top coat/Si substrate wafers.

Type
Articles
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.Vincenzini, P., Forum on New Materials, Vol. H, Surface Engineering (Techna Srl, Faenza, Italy, 1999).Google Scholar
2.Stoney, G.G., Proc. R. Soc. London 82, 172 (1909).Google Scholar
3.Chu, S.N.G, Macrander, A.T., Strage, K.E., and Johnston, W.D. Jr, J. Appl. Phys. 57, 249 (1985).CrossRefGoogle Scholar
4.Moyan, I.C. and Segmuller, C., J. Appl. Phys. 60(10), 2980 (1986).Google Scholar
5.Timoshenko, S., J. Opt. Soc. 11, 233 (1925).CrossRefGoogle Scholar
6.Davidenkov, N.N., Sov. Phys. Solid State 2, 2595 (1961).Google Scholar
7.Chu, S.N.G, J. Electrochem. Soc. 145, 3621 (1998).CrossRefGoogle Scholar
8.Chuang, T-J., Lee, S., and Wang, W-L. (unpublished work, National Tsing Hua University, Hsinchu, Taiwan, 1997).Google Scholar
9.Hibbeler, R.C., Mechanics of Materials Macmillian, New York, 1991), Sec. 6.4, Composite Beams, p. 281.Google Scholar
10.Timoshenko, S., Strength of Materials, Part I, Elementary Theory and Problems, 3rd ed., (D. Van Nostrand Co., Inc., Princeton, NJ, 1955), Sec. 47, p. 217.Google Scholar
11.Jou, J-H., Res. Rep on General Formula for Internal Stresses and Curvature Radius in Multilayer Structures—Consideration of Processing Condition RJ 6058 (60191) in Physics (IBM Research Division, San Jose, CA, 1988).Google Scholar
12.Tu, K.N., Mayer, J.W., and Feldman, L.C., Electronic Thin Film Science For Electrical Engineers and Materials Scientists (Macmillian, New York, 1992), Chap. 4.Google Scholar