Title :
Electron Beam Evaporation of Tungsten Oxide Films for Gas Sensors
Author :
Tesfamichael, T.
Author_Institution :
Fac. of Built Environ. & Eng., Queensland Univ. of Technol., Brisbane, QLD, Australia
Abstract :
Pure and iron incorporated nanostructured Tungsten Oxide (WO3) thin films were investigated for gas sensing applications using noise spectroscopy. The WO3 sensor was able to detect lower concentrations (1-10 ppm) of NH3, CO, CH4, and Acetaldehyde gases at operating temperatures between 100°C to 250°C. The iron-doped Tungsten Oxide sensor ( WO3:Fe) showed some response to Acetaldehyde gas at relatively higher operating temperature (250°C) and gas concentration of 10 ppm. The sensitivity of the WO3 sensor towards NH3, CH4 and Acetaldehyde at lower operating temperatures (50°C-100°C) was significant when the sensor was photo-activated using blue light-emitting diode (Blue-LED). From the results, photo-activated WO3 thin film that operates at room temperature appeared to be a promising gas sensor. The overall results indicated that the WO3 sensor exhibited reproducibility for the detection of various gasses and the WO3:Fe indicated some response towards Acetaldehyde gas.
Keywords :
electron beam applications; gas sensors; light emitting diodes; spectroscopy; tungsten compounds; WO3; acetaldehyde gas; blue light-emitting diode; blue-LED; electron beam evaporation; gas sensors; iron incorporated nanostructures; iron-doped tungsten oxide sensor; noise spectroscopy; operating temperatures; temperature 50 degC to 250 degC; Electron beams; Gas detectors; Gases; Iron; Light emitting diodes; Spectroscopy; Temperature sensors; Thin film sensors; Transistors; Tungsten; Gas sensor; iron doping tungsten oxide; nanostructured thin films; noise spectroscopy;
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2010.2048427
