Hostname: page-component-7479d7b7d-767nl Total loading time: 0 Render date: 2024-07-13T16:28:57.422Z Has data issue: false hasContentIssue false

Measurement of the Effect of Temperature on Stress Distribution and Deformation in Multilayer Optical Thin Film Structures

Published online by Cambridge University Press:  21 February 2011

Cynthia G. Madras
Affiliation:
Tufts University, Thermal Analysis of Materials Processing Laboratory, Department of Mechanical Engineering, Medford, MA, 02155. Raytheon Research Division, Lexington, MA, 02173.
P. Y. Wong
Affiliation:
Tufts University, Thermal Analysis of Materials Processing Laboratory, Department of Mechanical Engineering, Medford, MA, 02155.
I. N. Miaoulis
Affiliation:
Tufts University, Thermal Analysis of Materials Processing Laboratory, Department of Mechanical Engineering, Medford, MA, 02155.
L. M. Goldman
Affiliation:
Raytheon Research Division, Lexington, MA, 02173.
Get access

Abstract

This study investigates methods of predicting the deformation and stress distribution in multilayer optical thin film structures. The thin film layers include materials of various thermal expansion coefficients, elastic moduli, and melting temperatures. Each layer is deposited at a different temperature, causing complex thermal and deposition stresses throughout the structure. In addition, since the deposition temperatures of some of the layers are high (>600°C), stress relaxation and plastic flow may occur in materials with low melting temperatures. A combination of theoretical predictions and experimental measurements is used to measure and quantify the deformation caused by residual and thermal stresses in the films as well as any plastic deformation that may have occurred. Results from a model using multilayer plate bending theory to determine the elastic deformation of the device due to thermal stresses are reported. These predictions, as well as a more common method of predicting film stress and curvature, are compared to experimentally measured curvature changes as a function of temperature in the samples. However, when plastic deformation begins to occur at high temperatures, the residual stress and degree of deformation are no longer predictable based on elastic theory alone, and have to be measured experimentally. Plastic deformation in the substrate is discussed as a cause of a high observed curvature following sample heating.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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

1. D’Heurle, F.M. and Harper, J.M.E., Thin Solid Films 171, 8992 (1989).Google Scholar
2. Marks, N.A, Guan, P., McKenzie, D.R, and Pailthorpe, B. A, “Molecular dynamics study of ion impact phenomena and compressive stress in thin films”,(Mater. Res. Soc. Proc., Fall 1993).Google Scholar
3. Townsend, P.H., Barnett, D.M., and Brunner, T.A, J. Appl. Phys. 62 (11), 44384444 (1987).Google Scholar
4. Suhir, E., J. Appl. Mech., 55 143148 (1988).Google Scholar
5. Klein, C., “Thermal Stress Modeling for Diamond-Coated Optical Windows”, SPIE Optical Materials for High-Power Lasers, (Proceedings of the 1990 SPIE Symposium, Bellingham, WA 1991).Google Scholar
6. Ashby, M.F. and Jones, D., Engineering Materials I: An Introduction to their Properties and Applications, (Pergamon Press, Oxford, 1980).Google Scholar
7. Field, J.E., The Properties of Diamond, (Academic Press, London, 1979).Google Scholar
8. DeBeers Industrial Diamond Division flyer, “The Properties of Diamond”Google Scholar
9. Comprehensive Inorganic Chemistry, Edited by Trotman-Dickinson, A.F., (Pergamon Press, Elmsford, NY, 1973).Google Scholar
10. Kirby, R., Hahn, T., and Rothrock, B., “Thermal Expansion” American Institute of Physics Handbook, (McGraw-Hill, New York, NY, 1972).Google Scholar
11. Slack, G.A. and Bartram, S.F., J. Appl. Phys. 46 (1), 8998 (1975).Google Scholar
12. Kingery, W.D., Bowen, H.K., and Uhlmann, D.R., Introduction to Ceramics. (John Wiley & Sons, New York 1976), pp.707709.Google Scholar
13. Isomae, S., Nanba, M., Tamaki, Y., and Maki, M., Applied Physics Letters 30 (11), 564566 (1977).Google Scholar
14. Rosenberg, S., Wong, P.Y., and Miaoulis, I.N., “Thermal and Deposition Stress Relaxation in Low-Melting Point Substrates with High-Melting Point Films”, Thermal Processing of Materials: Thermo-Mechanics, Controls, and Composites, (ASME 1994 Proceedings HTD-289, p.1 1994).Google Scholar