[Zurück]

J. Sama, S. Barth, G. Domènech-Gil, J. Prades, N. Lopez, O. Casals, F. Hernandez-Ramirez, I. Gracia, C. Cane, A. Romano-Rodriquez:
"SnO2 NWs network site-selectively synthesised as ammonia sensor in dry and humid air";
Poster: EMRS Spring Meeting, Lille; 02.05.2016 - 06.05.2016; in: "EMRS Spring Meeting 2016", (2016).

Nanostructures as nanowires (NW) or nanotubes (NT) are highly interesting morphologies for gas sensors due to the high surface to volume ratio [1], which leads to enhance the transduction of the interaction between their surface and the surrounding gas molecules into a change in their electrical resistance. An important drawback of fabricating electronic devices based on nanowires as building blocks using bottom-up approaches is the integration, which is difficult, time consuming and expensive. Site-selective growth of SnO2 has been performed on top of CMOS compatible micromembranes that contain a microheater which provides the thermal energy necessary for the growth. Synthesis of NWs is carried out by a localized Chemical Vapor Deposition process using Au as a catalyst, in a fast, and low power consumption process. The network of NWs is fabricated on micromebranes without employing a mask and no post-processing is needed to use the network as a gas sensor. The SnO2 NWs-based devices have been characterized towards several tens of ppm of NH3 in dry and humid conditions. The ammonia response is diminished and slowed down in presence of water vapour. The sensing kinetics at different temperatures have been analysed, allowing to identify the concurrent mechanisms. A response time of less than a minute and good repeatability of ammonia response are obtained from the characterization of the sensor.