Fabrication of Highly Sensitive NH3 Sensor Based on Mixed In2O3 – AgxO Nanostructural Thin Films deposited on porous silicon

Abstract

A highly sensitive NH3 gas sensor of mixed In2O3 – AgxO nanostructure thin films deposited on porous silicon were synthesized by chemical spray pyrolysis technique. The structure of the sensor thin films is analyzed by XRD, AFM and FE-SEM techniques. The nanostructure polycrystalline thin films with average grain size between (93.56 and 57.75) nm, from AFM results. The sensitivity of the synthesized gas sensors toward 400 ppm NH3 is obtained a high value in the low operating temperature, which ranged between (77.57%-98.66%) with low response and recovery times, ranged between (11.9-15.19) s and (8.6-25.22) s respectively. These high sensor properties are due to the porous silicon substrate.