Skip to main content Accessibility help
×
Home

Porous silicon thin film gas sensor

  • I. Ferreira (a1), E. Fortunato (a1) and R. Martins (a1)

Abstract

The performances of amorphous and nano-crystalline porous silicon thin films as gas detector are pioneer reported in this work. The films were produced by the hot wire chemical vapour deposition (HW-CVD). These films present a porous like-structure, which is due to the uncompensated bonds and oxidise easily in the presence of air. This behaviour is a problem when the films are used for solar cells or thin film transistors. For as gas detectors, the oxidation is a benefit, since the CO, H2 or O2 molecules replace the OH adsorbed group. In the present study we observe the behaviour of amorphous and nano-crystalline porous silicon thin films under the presence of ethanol, at room temperature. The data obtained reveal a change in the current values recorded by more than three orders of magnitude, depending on the film preparation condition. This current behaviouris due to the adsorption of the OH chemical group by the Si uncompensated bonds as can be observed in the infrared spectra. Besides that, the current response and its recover time are done in few seconds.

Copyright

References

Hide All
[1] Francia, G. Di, Filippo, F. De, Ferrar, V. La, Quercia, L., Lencellotti, L., Baratto, C., Comini, E., Faglia, G., Sberveglieri, G., Proceeding of the 12th European Conference on Solid-StateTransducers and the 9th UK conference on Sensors and their Applications, Southampton, UK, 13-16 September 1998 (edited by White, N. M., Institute of Physics Publishing Bristol and Philadelphia), vol1, p.544.
[2] Barillaro, G., Diligenti, A., Nannini, A., Pieri, F., Book of Extended Abstracts of 14th European Conference on Solid-State Transducers, 27-30 August, 2000, Copenhagen (edited byReus, Rogerde and Bowstra, Siebe, Mikroelektronik Centret, Denamark 2000) pag. M2P39.
[3] Heiland, G., Sensors and Actuatos, 2, 343 (1982).
[4] Vasiliev, R. B., Raybova, L. I., Rumyantseva, M. N. and Gaskov, A. M., Book of Extended Abstracts of 14th European Conference on Solid-State Transducers, 27-30 August, 2000, Copenhagen(edited by Reus, Roger de and Bowstra, Siebe, Mikroelektronik Centret, Denamark 2000) pag. T1S2.
[5] Fereira, I., Fernandes, B. and Martins, R., Vacuum, 52, 147 (1999); I. Ferreira, A. Cabrita, F. Braz Fernandes, E. Fortunato and R. Martins, To be published in Vacuum, 2001.
[6] Martins, R., Ferreira, I., Fernandes, F. and Fortunsto, E., Journal of Non-Crystalline Solids, 227–230, 901 (1998).
[7] Vancu, Ana, Ionescu, Radu and Nicolae Bêrsan, in Thin Film Resistive Sensors, ed. By Ciureanu, P. and Middelhoek, S., Institute of Physics Publishing, Bristol, Philadelphia and New York, 1992, cap 6, p.437.
[8] Morrison, S. Roy, Sensors and Actuators, 2, 329 (1982).10.1016/0250-6874(81)80054-6

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed