Hostname: page-component-76fb5796d-x4r87 Total loading time: 0 Render date: 2024-04-26T20:16:08.427Z Has data issue: false hasContentIssue false
  • English
  • Français

Film Stress Influence of Bilayer Metallization on the Structure of RF MEMS Switches

Published online by Cambridge University Press:  10 February 2011

R. E. Strawser ,
R. Cortez ,
M. J. O'Keefe ,
K. D. Leedy ,
J. L. Ebel  and
H. T. Henderson
R. E. Strawser
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, OH 45433, Richard.Strawser@wpafb.af.mil
R. Cortez
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, OH 45433, Richard.Strawser@wpafb.af.mil
M. J. O'Keefe
Affiliation:
Univ. of Missouri-Rolla, Dept. of Metallurgical Engineering, Rolla, MO 65401
K. D. Leedy
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, OH 45433, Richard.Strawser@wpafb.af.mil
J. L. Ebel
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, OH 45433, Richard.Strawser@wpafb.af.mil
H. T. Henderson
Affiliation:
Univ. of Cincinnati, Dept. of Electrical & Computer Engineering and Computer Science, Cincinnati, OH 45221
Get access

Abstract

The performance of microelectromechanical systems (MEMS) switches is highly dependent on the switches' constituent materials. The switch material must be able to provide both structural integrity and high electrical conductivity. Cantilever beams, doubly clamped beams, and membranes are typical MEMS structures used in microwave/millimeter wave applications. In this study, cantilever and doubly clamped beam microswitches were fabricated on GaAs substrates using evaporated bilayers of titanium and gold metallization in which the total thickness was held constant at 1.5 μm while the gold thickness varied from 0.5 μm to 1.5 μm. The lengths of the cantilevers varied from 300 to 500 μm and the doubly clamped beams varied from 600 to 800 μm. An upward deflection of the gold dominated cantilever beams indicated an increasing tensile stress gradient. Results of microwave characterization demonstrated higher switch isolation (off-resistance) for shorter beam switches at the expense of higher insertion loss (on-resistance) and actuation voltage. A discussion of the observed released microswitch structure within the context of the measured film stresses and electrical performance will be presented.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 594: Symposium V – Thin Films - Stresses & Mechanical Properties VIII , 1999 , 213
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. Eddy, D.S. and Sparks, D.R., Proceedings of the IEEE, Vol. 86, No. 8, 1747 (1998).Google Scholar
2. Mastrangelo, C.H., Burns, M.A., and Burke, D.T., Proceedings of the IEEE, Vol. 86, No. 8, 1769 (1998).Google Scholar
3. Brown, E.R., IEEE Trans. on Microwave Theory and Tech., Vol. 46, No. 11, 1868 (1998).Google Scholar
4. Nguyen, C.T.C., Katehi, L.P.B., and Rebeiz, G.M., Proceedings of the IEEE, Vol. 86, No. 8, 1756 (1998).Google Scholar
5. Williams, R., Modern GaAs Processing Methods, (Artech House, 2nd ed., 1990), p. 162, 272.Google Scholar
6. Larson, L.E., Hackett, R.H., Melendes, M.A., and Lohr, R.F., IEEE 1991 Microwave and Millimeter-wave Monolithic Circuits Symposium, 27 (1991).Google Scholar
7. Yao, J.J. and Chang, M.F., IEEE Transducers 95, 384 (1985).Google Scholar
8. Goldsmith, C., Yao, Z., Eshelman, S., and Denniston, D., IEEE Microwave Guided Wave Letters, Vol. 8, No. 8, 269 (1998).Google Scholar
9. Pacheco, S., Nguyen, C.T., and Katehi, L.P.B., 1998 IEEE MTT-S Int. Microwave Symposium Digest, 1569 (1998).Google Scholar
10. Chang, K., Handbook of Microwave and Optical Components: Volume 2 Microwave Solid- State Components, (John Wiley & Sons, 1990), p. 230–262.Google Scholar
11. Lee, J., Zych, D., Reese, E., and Drury, D., IEEE Trans. On Microwave Theory and Techniques, Vol. 43, 250 (1995).Google Scholar
12. Shokrani, M. and Kapoor, V.J., IEEE Trans. on Microwave Theory and Tech., Vol. 42, 772 (1994).Google Scholar
13. Williams, R., Modern GaAs Processing Methods, (Artech House, 2nd ed., 1990), p. 64.Google Scholar
14. Tal, N., Sonnenberg, T., Jansen, H., Legtenberg, R., and Elwenspoek, M., Micromechanics, J. and Microengineering, Vol. 6, 385 (1996).Google Scholar