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Atomic Force Microscopy Structural Characterization of Polyaniline Thin Film Sensors

Published online by Cambridge University Press:  22 February 2011

Jack Y. Josefowicz ,
Frederick G. Yamagishi  and
Camille I. van Ast
Jack Y. Josefowicz
Affiliation:
University of Pennsylvania, Department of Materials Science and Engineering, Philadelphia, PA 19104-6393 Hughes Research Laboratories, Exploratory Studies Laboratory, Malibu, CA 90265
Frederick G. Yamagishi
Affiliation:
Hughes Research Laboratories, Exploratory Studies Laboratory, Malibu, CA 90265
Camille I. van Ast
Affiliation:
Hughes Research Laboratories, Exploratory Studies Laboratory, Malibu, CA 90265
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Abstract

Using Tapping Mode Atomic Force Microscopy (TMAFM), the surface structure was determinedfor polymer sensors which incorporated polyaniline (PAn) films that were deposited electrochemically across narrow insulating gaps between interdigitated gold electrodes. The sensitivity and response time for such sensors, which can be used for the detection of low levels of gases and low concentrations of impurities in liquid media critically dependon the quality and structure of the polymer film in the gap region between the gold electrodes. TMAFM images of the PAn films ranging in thickness between ≈1.5μtmand ≈5μm reveal that films approaching 5μm (typically used in such sensors) develop deep cracks at the edges and along the length of the Au electrodes. Thecracks, which appear to be a consequence of stress build-up in thick films, can lead to reliability problems and inferior sensor performance. Simple modeling analysis of cracked films indicates that they can lower sensitivity and increase response time. TMAFM images of sensors with thinner ≈2.5μm PAn films show no cracks as well as continuous PAn bridges across the gap between Au electrodes. Analyses of TMAFM images are presented and compared for thin and thick film PAn sensors.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 338: Symposium – Materials Reliability in Microelectronics IV , 1994 , 605
Copyright
Copyright © Materials Research Society 1994

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References

REFERENCES

1. Bartlett, P.N., Archer, P.B.M. and Ling-Chung, S.K., Sensors and Actuators 19, 125 (1989).Google Scholar
2. Bartlett, P.N. and Ling-Chung, S.K., Sensors and Actuators 19, 141 (1989).Google Scholar
3. Bartlett, P.N. and Ling-Chung, S.K., Sensors and Actuators 20, 287 (1989).Google Scholar
4. Boyle, M.E. and Cozzens, R.F., Final Report NRL Memorandum Report 6482 June 12, 1989 (1989).Google Scholar
5. Couves, L.D. and Porter, S.J., Synth. Met. 28, C761 (1989).Google Scholar
6. Yamagishi, F.G., Ast, C.I. van and Miller, L.J., Patent pending.Google Scholar
7. Yamagishi, F.G., Ast, C.I. van and Miller, L.J., to be presented at the 1994 American Chemical Society National Meeting, Symposium on Transducer-Active Polymers: Components in Sensors and Acatuators, Washington D.C., August 21-26, 1994.Google Scholar
8. Yang, R., Evans, D.F., Christensen, L. and Hendrickson, W.A., J. Phys. Chem. 94, 6117 (1990).Google Scholar
9. Caple, G., Wheeler, B.L., Swift, R., Porter, T.L. and Jeffers, S., J. Phys. Chem. 94, 5639 (1990).Google Scholar
10. Mantovani, I.G., Warmack, R.J., Annis, B.K., MacDiarmid, A.G. and Scher, E.J., Appl. Polym. Sci. 40, 1693 (1990).Google Scholar
11. Kim, Y.T., Yang, H. and Bard, A.J., J. Electrochem.Soc. 138, L71 (1991).Google Scholar
12. Porter, T.L., Lee, C.Y., Wheeler, B.L. and Caple, G., J. Vac. Sci. Technol. A9, 1991 (1991).Google Scholar
13. Binning, G., Gerber, C., Stoll, E., Albrecht, T.R. and Quate, C.F., Europhys. Lett. 3, 1281 (1987).Google Scholar
14. Albrecht, T.R. and Quate, C.F., J. Appl. Phys. 62, 2599 (1987).Google Scholar
15. Josefowicz, J.Y., Maliszewskyj, N.C., Idziak, S.H.J., Heiney, P.A., McCauley, J.P. Jr, and Smith, A.B. III, Science 260, 323 (1993).Google Scholar
16. Albrecht, T.R. and Quate, C.F., J. Vac. Sci. Technol. A6, 271 (1988).Google Scholar
17.Digital Instruments, Santa Barbara, CA 93117.Google Scholar
18. Diaz, A.F. and Logan, J.A., J. Electroanal. Chem. 111, 111 (1980).Google Scholar
19. Kang, E.T., Neoh, K.G., Woo, Y.L., Tan, K.L., Huan, C.H.A. and Wee, A.T.S., Synth. Met. 53, 333 (1993).Google Scholar