A highly sensitive catalytic gas sensor for hydrogen detection based on sputtered nanoporous platinum

This paper presents a new thermal gas sensor for hydrogen detection based on a catalytic thin film made of sputtered nanoporous platinum. Due to an increased porosity of sputtered catalytic layers, sensitivity could remarkably be raised from commonly 6 V/ppm [1] up to 18 V/ppm. As sensing element a thermopile made of p-doped polysilicon and an alloy of tungsten titanium is used. A second thermopile is placed for reference measurement and reduced cross sensitivity on same membrane.