Electro-Deposited PdNi-Si Schottky Barrier Hydrogen Sensors with Improved Time Response

Hydrogen sensor based on electrodeposited PdNi-Si Schottky barriers have been fabricated with a gradient structure in the PdNi concentration in a single electrodeposition run through variation of the deposition potential. By varying the electrodeposition potential after a fixed amount of charge, we are able to create various Schottky barrier structures.The resulting sensors in the back to back diode configuration show very low idle leakage current and high sensitivity to hydrogen. The structure with increased Ni concentration at the PdNi-Si interface shows dramatically improved time response as compared to the sample with uniform PdNi concentration.