Abstract
We demonstrate that the soft e-beam lithography (soft-eBL) fabricated polycrystalline ZnO nanolines show reproducible response to ppm-level H2 and NO2 even at room temperature, due to the intrinsic Joule heating effect in such nanodevices. The Joule heating effect is confirmed by studying the resistance-temperature relationship of the sensor as well as the persistent photoconductivity phenomena in ZnO. We note that Joule heating increases the nanoline temperature to around 72 °C, which enhances the oxidation-reduction reaction at the ZnO surface. Therefore, the nanolines show faster photoresponse than the thin film. These results may help tailor and optimize gas sensor devices for improved performance.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 159-163 |
| Number of pages | 5 |
| Journal | Sensors and Actuators, B: Chemical |
| Volume | 144 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 29 2010 |
Funding
The author would like to thank Prof. T. Mason at Northwestern University for the helpful discussion and suggestion. This research work was primarily supported by US-DOE Award Number DE-FG02-07ER46444 . The sensor experimental set-up and software/hardware development was initially supported by NSF-NSEC Award Number EEC-0647560 . The research was performed in the EPIC facility of NUANCE Center at Northwestern University. NUANCE Center is supported by NSF-NSEC, NSF-MRSEC, Keck Foundation, the State of Illinois, and Northwestern University.
Keywords
- Gas sensor
- Room temperature gas sensing
- UV light
- ZnO
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Instrumentation
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry