Sn02 nanorods were successfully deposited on 3" Si/Si02 wafers by inductively coupled plasma-enhanced chemical vapor deposition (PECVD) and a wafer-level patterning of nanorods layer for miniaturized solid state gas sensor fabrication were performed. Uniform needle-shape Sn02 nanorods in situ grown were obtained under catalyst- and high temperature treatment-free growth condition. These nanorods have an average diameter between 5 and IS nm and a length of 160 to 300 nm. The Sn02-nanords based gas sensors were tested towards NH3 and CH30H and gas sensingtests show remarkable response, showing promising and repeatable results compared with the Sn02 thin films gas sensors.

SnO(2) nanorods were successfully deposited on 3" Si/SiO(2) wafers by inductively coupled plasma-enhanced chemical vapour deposition (PECVD) and a wafer-level patterning of nanorods layer for miniaturized solid state gas sensor fabrication were performed. Uniform needle-shaped SnO(2) nanorods in situ grown were obtained under catalyst- and high temperature treatment-free growth condition. These nanorods have an average diameter between 5 and 15 nm and a length of 160-300 nm. The SnO(2)-nanorods based gas sensors were tested towards NH(3) and CH(3)OH and gas sensing tests show remarkable response, showing promising and repeatable results compared with the SnO(2) thin films gas sensors.

Breath analysis, an innovative non-invasive diagnostic technique, bears the potential of drastically reducing the costs of medical diagnostics offering a simple alternative to standard blood analysis. Here, a flame spray pyrolysis (FSP) reactor was used for synthesis and direct deposition of nanostructured metal oxide (MOx) films onto microsensor substrates. These sensors were assembled in an array and tested simultaneously for different analytes requiring low power consumption to heat the sensor to the operating target temperature. The sensors had varying responses to the different analytes depending on sensing material (e.g. SnO2, WO3, ZnO), facilitating improvements on the selectivity of specific analytes (e.g. acetone, methanol, isoprene).

ZnO nanocrystals (2.5-4.5 nm) were prepared by a wet chemical method based on alkaline-activated hydrolysis and condensation of zinc acetate solutions. Dropcasting of the nanocrystals onto alumina substrates allowed the fabrication of gas sensing devices, that were tested towards NO2, acetone and methanol and showed promising results. At low working temperature, the ZnO quantum dots based sensors are selective to nitrogen oxide, in fact a good sensitivity is shown at 200 degrees C at low concentration (2 ppm), while at temperature above 350 degrees C, high responses are obtained for acetone and methanol. The results obtained are stimulating for further developing of nano-ZnO based sensor devices.