Hostname: page-component-848d4c4894-ttngx Total loading time: 0 Render date: 2024-05-17T19:33:12.040Z Has data issue: false hasContentIssue false

Unusual high sensitivity in highly oriented laser ablated thin films of SnO2 on (1102) sapphire and (100) LaAlO3

Published online by Cambridge University Press:  15 April 2002

K. I. Gnanasekar
Affiliation:
Surface Science, Spectroscopy and Solid State Ionics Laboratory, Department of Physics, Southern University A&M College, Bâton Rouge, Louisiana 70813, USA
B. Rambabu*
Affiliation:
Surface Science, Spectroscopy and Solid State Ionics Laboratory, Department of Physics, Southern University A&M College, Bâton Rouge, Louisiana 70813, USA
K. C. Langry
Affiliation:
Chemical and Biological Detection Group, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
Get access

Abstract

A systematic investigation on growth and sensor characteristics of SnO2 thin films of different orientations is reported for the first time. Thin films were grown by pulsed laser (KrF; λ = 248 nm) ablation technique under in-situ conditions. Films deposited at 525 °C on (1102) sapphire were predominantly (101) orientated whereas those deposited on (100) LaAlO3 were highly a-axis orientated. Sensors made of predominantly (101) oriented films exhibited more than two orders magnitude change in resistance even for 100 ppm of H2 in air at 310 °C. The response and retracing times of the sensor were remarkably short respectively 30 and 200 s. Sensors made of a-axis oriented films also exhibited similar sensitivity and response time for the same quantity of both H2 and LPG. However, the retrace time was very long typically about 20 min. Atomic force microscopic (AFM) investigation reveals that the films are highly granular with an average size of about 100–150 nm which is ten times larger than the critical size of 6 nm, a criterion required for high sensitivity. (The Debye length of ${\rm SnO}_2 \cong 3.07$ nm at 293 K and the critical grain size is therefore 2 × Debye length, which is 6 nm.)

Keywords

Type
Research Article
Copyright
© EDP Sciences, 2002

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

Dai, C.M., Su, C.S., Chuu, D.S., Appl. Phys. Lett. 57, 1879 (1990). CrossRef
Murty, N.S., Bhagawat, G.K., Jawalekar, S.R., Thin Solid Films 92, 347 (1982). CrossRef
Pommier, R., Gril, C., Marucchi, J., Thin Solid Films 77, 91 (1981). CrossRef
Beensh-Marchwicka, G., Krol-Stepniewska, L., Misink, A., Thin Solid Films 113, 215 (1984). CrossRef
Goodchild, R.G., Webb, J.B., Williams, D.F., J. Appl. Phys. 57, 2308 (1985). CrossRef
P.T. Moseley, B.C. Tofield, Solid state gas sensors (Adam Hilger, Bristol and Phiadelphia, 1987).
Williams, D.E., Sens. and Actuators B 57, 1 (1999). CrossRef
Barsan, N., Schweizer-Berberich, M., Gopel, W., J. Anal. Chem. 365, 287 (1999). CrossRef
D.E. Williams, Conduction and gas response of semiconductor gas sensors, edited by P.T. Mosley, B.C. Tofield, Solid state gas sensors (Adam Hilger, Bristol, 1987), p. 71.
N. Yamazoe, N. Miura, Some basic aspects of semiconductor gas sensors, edited by Yamamuch, Chemical sensor technology (Kodansha, Tokyo, 1992), Vol. 4, p. 20.
Leary, D.J., Barnes, J.O., Jordan, A.G., J. Electrochem. Soc. 129, 1383 (1981).
J. Cheung, J. Horwitz, MRS Bull. 17, 231(1992).
Windischmann, H., Mark, P., J. Electrochem. Soc. 126, 627 (1979). CrossRef
Williams, G., Coles, G.S.V., MRS Bull. 24, 25 (1999). CrossRef
Semancik, S., Cavocchi, R.E., Thin Solid Films 206, 81 (1991). CrossRef
M. Egashira, Y. Yoshida, S. Kawasumi, Proc. Third Int. Conf. On Solid State Sensors and Actuators, Philadelphia, PA, 1985, IEEE, Piscataway, NJ, (1985), p. 397.
M. Egashira, T. Matsumoto, H. Katsuki, H. Iwanaga, Proc. Second Int. Meet. On Chemical Sensors, Bordeaux, 1986, p. 213.
G. Heiland, D. Kohl, T. Seiyama, Chemical sensor technology (Elsevier, Amsterdam, 1988), Vol. 1, p. 15.
Fryberger, T.B., Semancik, S., Sens. and Actuators B 2, 377 (1990). CrossRef
N. Yamazoe, Proc. Third Int. Meet. On Chemical Sensor, Cleveland, OH, 1990, p. 3.
Mitzei, J., Sens. and Actuators B 23, 173 (1995).
Rembeza, S.I., Rembeza, E.S., Svistova, T.V., Borsiakova, O.I., Phys. Stat. Sol. 179, 147 (2000). 3.0.CO;2-N>CrossRef
Summitt, R., J. Appl. Phys. 39, 3762 (1968). CrossRef