Berlin 2008 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 15: Devices
HL 15.2: Vortrag
Montag, 25. Februar 2008, 11:30–11:45, ER 164
SnO2-nanostructures for gas sensing applications — •Alexandra Tischner1, Anton Köck1, Thomas Maier1, Michael Kast1, Christoph Stepper1, Judith Januschewsky2, Christian Edtmaier2, Christian Gspan3, and Gerald Kothleitner3 — 1Austrian Research Centers GmbH - ARC, Nano-Systemtechnologien, Wien, Österreich — 2Institut für Chemische Technologien und Analytik, Nano-Werkstoffe, Technische Universität Wien, Österreich — 3Zentrum für Elektronenmikroskopie, Graz, Österreich
Gas sensors based on nanocrystalline SnO2 films and single-crystalline SnO2-nanowires have been developed. The films with a thickness of 30-100 nm are fabricated by a spray pyrolysis process on SiO2-coated Si-substrates and processed in arrays of parallel bars, which are connected on both ends by ohmic metal contacts. The operating mode is based on a change in the electrical conductance along the SnO2-bars due to reducing or oxidizing gases. The sensors are operated at 200-400∘C, show high sensitivity to humidity and are able to detect CO down to a concentration of 5 ppm. The SnO2-nanowires are fabricated by tempering 150-300 nm thick SnO2 films at temperatures of 800-1000∘C. This process results in growth of SnO2-nanowires with 30-400 nm diameter and length up to several 100 µm. TEM analysis proves the single crystallinity of the nanowires. The SnO2-nanowires are deposited on SiO2-coated Si-substrates and contacted by means of photolithography. Investigations of the sensor performance of nanowires in comparison to nanocrystalline SnO2 films are in progress.