Micro structural characterization and gas sensing behaviour of In2O3:Ag nano composite thin films deposited by electron beam evaporation technique

Abstract

The main objective in this discussion is to investigate the role of metal additives in In2O3 to detect the toxic gases. Ag-In2O3 nano composite thin films were grown by electron beam evaporation. In2O3:Ag nano composite thin films were deposited on quartz substrate by electron beam evaporation technique at a substrate temperature of 350°C, with deposition time 10mts and electron gun power of 75 W. The vacuum chamber was evacuated to a base vacuum of 6x10−6 Torr and oxygen partial pressure was maintained at 0.1 mTorr. GIXRD patterns confirmed the formation of polycrystalline films with cubic structure of (222) plane direction for In2O3 and (111) orientation for Ag2O. Thickness of the films was estimated by stylus profilometer. SEM micrographs of pure In2O3 films shows spherical shaped grain morphology and after adding Ag to In2O3 grain morphology changes to helical structure with an increase in grain size. All the above synthesized thin films have been tested for sensing of volatile organic compound (VOC) gases. The In2O3:Ag nano composite thin films deposited on quartz substrate have shown better response to volatile organic compound gases.