Effect of Diffusion of I Group Metal (Ag) on Characteristics of Metal/Porous Silicon Sensors

Abstract

Current-voltage characteristics of Schottky-type Ag/Porous Silicon (Ag/PS) structures in normal air, humid ambient and in different hydrogen-containing solutions (distilled water, freshwater, Black sea-water, ethanol ad methanol) have been investigated. Generation of the opencircuit voltage (Voc), short-circuit current (Jsc) up to 560 mV and 0.5mA/cm2, respectively, on placing Ag/PS structures in hydrogen-containing solutions was discovered. This phenomenon is reversible, i.e. placing and removal of Ag/PS structures cell from hydrogen-containing solutions is accompanied by response and recovery of the Voc and Jsc parameters. It is shown that the thermal annealing of the Ag/PS structure at 200oC for 10 min is accompanied by somewhat changes and stabilization of Voc and Jsc parameters of Ag/PS sensors. The possible mechanisms related with hydrogen-stimulated generation of voltage and diffusion-stimulated stabilization of the sensing parameters of Ag/PS Schottky-type structures is suggested. Data received in this work indicate on perspectivity of using Ag/PS structures as both the gas sensors and hydrogen cells.