A new Pd-InP Schottky hydrogen sensor fabricated by electrophoretic deposition with Pd nanoparticles

In this letter, a new Pd-InP Schottky diode hydrogen sensor fabricated by electrophoretic deposition (EPD) combined with nanosized Pd particles is first proposed and demonstrated. Experimentally, the studied device exhibited excellent current-voltage rectifying characteristics with a large Schottky barrier height (SBH) of 829 meV. At 303 K, a high saturation sensitivity ratio of 38 was found under a very low hydrogen concentration of 15 ppm H-2 /air. As raising the hydrogen concentration to 1.0% H2/air, the SBH lowering of the studied device reached to 307 meV and the sensitivity ratio was high as 1.29 x 10(5) with a very rapid response, which far prevailed over those fabricated by the conventional thermal evaporation and electroless plating techniques. Consequentially, the EPD Pd-InP Schottky diode with extremely effective I'd gate is promising for the fabrication of high-performance hydrogen sensors.