INVESTIGATION OF PD-CU-SI METALLIC GLASS FILM FOR HYSTERISIS-FREE AND FAST RESPONSE CAPACITIVE MEMS HYDROGEN SENSORS

We show that PdCuSi metallic glass (MG) is a promising material for Pd-based capacitive MEMS hydrogen sensors, reducing both hysteresis and response time of the sensing operation. Firstly, we demonstrate that the fabricated PdCuSi MG film exhibits no hysteresis during hydrogen absorption and desorption. Drastic reduction of the response time is also shown. We also show that, to eliminate the hysteresis and to reduce the response time, PuCuSi needs to be MG, not microcrystal. Secondly, based on the measured strain property, we show that the capacitive sensing scheme has advantage in sensing low concentration hydrogens.