| Autor: |
Kennedy, M. K., Kruis, F. E., Fissan, H., Mehta, B. R., Stappert, S., Dumpich, G. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 1/1/2003, Vol. 93 Issue 1, p551, 10p, 3 Black and White Photographs, 2 Diagrams, 2 Charts, 8 Graphs |
| Abstrakt: |
In order to investigate the change of gas-sensitive properties of undoped tin oxide nanoparticle films depending on particle size, a thin film synthesis technique has been developed. Well-defined tin oxide nanoparticles have been prepared using a gas-phase condensation method. Pure SnO was used as starting material and was evaporated at T=820 °C. The resulting particles were sintered and crystallized in-flight at T=650 °C. Size-selected nanoparticles ranging from 10 to 35 nm were produced to form a nanoparticle film by means of electrostatic precipitation or low pressure impaction. The effect of in-flight oxidation, sintering, and crystallization on the structure, size, and size distribution of nanoparticles have been studied in detail. The samples show n-type semiconductors' behavior like bulk SnO[sub 2]. The influence of particle size on gas sensitivity and response behavior is investigated for C[sub 2]H[sub 5]OH at operating temperatures 200-300 °C using silicon substrates having an interdigitated contact pattern and an integrated heating system. In the range of 10-35 nm it has been shown unambiguously that decreasing the particle size of tin oxide particles leads to an increase of the sensitivity and a more rapid response on changing gas conditions. The effect is especially clear for films with a particle size of 20 nm or smaller. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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