Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-27T01:54:47.890Z Has data issue: false hasContentIssue false

Piezoresistive Properties of Ceramic Strain Sensors with Controlled Nanoporosity

Published online by Cambridge University Press:  01 February 2011

Otto J. Gregory
Affiliation:
Sensors and Surface Technology Partnership Chemical Engineering Department, University of Rhode Island, Kingston, RI 02881
Tao You
Affiliation:
Sensors and Surface Technology Partnership Chemical Engineering Department, University of Rhode Island, Kingston, RI 02881
Get access

Abstract

A ceramic strain gage based on reactively sputtered indium tin oxide thin films is being developed to monitor the structural integrity of components employed in aerospace propulsion systems that operate at temperatures in excess of 1500°C. When relatively thick indium-tin-oxide (ITO) strain gages were prepared by reactive sputtering in oxygen:argon atmospheres and annealed in nitrogen, an extremely stable piezoresistive response was observed at temperatures as high as 1530°C. SEM and AFM of these sensor surfaces after high temperature exposure revealed a partially sintered microstructure with interconnected nanoporosity. Specifically, the microstructure consisted of a contiguous network of uniform sized ITO particles with well-defined necks between individual particles. When these microstructures were compared to those of relatively thin ITO sensors sputtered in nitrogen:argon:oxygen atmospheres, i.e. ITO films prepared in a nitrogen rich plasma, the average pore size and particle size was estimated to be an order of magnitude smaller than those associate with thick ITO sensors. In the nitrogen sputtered films, enhanced electrical conduction along the surfaces of the contiguous ITO particles resulted in a very stable and large piezoresistive response with a gage factor of 11.4 and a drift rate of 0.0001%/hour at 1560°C. The improved performance realized when the ITO films were processed in nitrogen may be extended to other ITO based sensors including gas sensors and the advantages of films processed in this manner will be discussed.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

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. Gregory, O.J., You, T. and Platek, M.J., Proceedings of 49th International Instrumentation, Systems and Controls Symposium, Orlando, Florida, USA, May 2003 Google Scholar
2. Dyer, S.E., Gregory, O.J., Amons, P.S. and Slot, A. B., Thin Solid Films 288, 279 (1996).10.1016/S0040-6090(96)08865-7Google Scholar
3. Gregory, O. J., Slot, A B., Amons, P.S. and Crisman, E.E., Surface and Coatings Technology 88, 78 (1996).Google Scholar
4. Gregory, O.J., Cooke, J.D. and Bienkiewicz, J.M., NATO-AGARD Advanced NonIntrusive Instrumentation for Propulsion Engines, Belgium October 1997.Google Scholar
5. Gregory, O.J., NASA Annual Technical Report-Aerospace Propulsion and Power Program NRA-01-GRC-02. 20012002.Google Scholar
6. Gregory, O.J., and Luo, Q., Sensors and Actuators A, 88, 234 (2001).10.1016/S0924-4247(00)00513-6Google Scholar
7. Gregory, O.J., Luo, Q., Bienkiewicz, J.M., Erwin, B.W., and Crisman, E.E., Thin Solid Films, 405, 263 (2002).10.1016/S0040-6090(01)01703-5Google Scholar
8. Lei, J.F. and Will, H.A., Sensors and Actuators A, 65, 187 (1998).10.1016/S0924-4247(97)01683-XGoogle Scholar
9. Nadaud, N., Nanot, M., Boch, P., J. Amer. Ceramic Society, 77, 843 (1994).10.1111/j.1151-2916.1994.tb05376.xGoogle Scholar
10. Gregory, O.J., You, T, Platek, M. and Crisman, E., Materials Research Society Symposium Proceedings 751, Z3.33 2003 10.1557/PROC-751-Z3.33Google Scholar