The change in electrical resistance of Pt thin films on glass substrates upon exposure to hydrogen gas at room temperature was studied. The effect was detectible only for film thicknesses of less than 40 nm, and increased with decreasing thickness. Samples were also produced with a Ti film inserted between the Pt film and the glass substrate as an adhesive layer. Although the Ti film did not react with the hydrogen gas, its presence reduced the resistance change effect because it acted as a parallel resistance. To overcome this problem, the surface of the glass substrate was nanostructurally modified using porous SiO2, which led to a larger resistance change ratio. To improve the recovery time, heating by pulsed current injection was carried out. A structure consisting of Pt (5nm)/Ti (3 nm)/porous SiO2/glass was found to show a clear response to hydrogen concentrations down to about 100 ppm at room temperature.
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Publication status||Published - 2014|
ASJC Scopus subject areas
- Physics and Astronomy(all)