Photomodulated thermoreflectance detection of hydrogen gas using optically thin palladium film on silicon oxide
Date
1998ISSN
0034-6748Source
Review of Scientific InstrumentsVolume
69Issue
3Pages
1505-1511Google Scholar check
Keyword(s):
Metadata
Show full item recordAbstract
The sensitivity various thicknesses of optically thin film palladium layers evaporated onto silicon oxide substrate is investigated in the presence of a hydrogen/air atmosphere at room temperature. The magnitude of the resulting reflectivity change is measured using an excite-probe technique, through laser excited photothermal modulation of a probe beam. This allows for the recovery of information from both the amplitude and phase channels of the hydrogen sensor output. Data indicates that concentrations of 0.1% hydrogen in the presence of a balanced air mixture and room temperature may be measured with an 8 nm palladium film. The presence of inhomogeneities the palladium layers leads to anomalous behavior. (C) 1998 American Institute of Physics.