Copper Doping Effect on Nanocrystalline Tin Oxide (SnO2) Thin Films for Gas Sensing Applications

Abstract

In this work, Nanocrystalline SnO2 and copper doped SnO2 with (SnO2:Cu, Cu: 1%, 3%, 5%) was grown on glass substrates at (350 °C) via chemical pyrolysis method. The results of the structural properties using XRD analysis showed that The films have diffraction angles of different intensities and have a tetragonal crystal structure. The intensity decreases with an increased doping ratio. Atomic force microscopy showed that with increasing copper doping, the average grain size decreased. Transmittance of the prepared films is greater than 70% at 550 nm. The energy gap of the calculated tin oxide is 3.9 eV and decreases with increasing copper doping, while the absorption coefficient increases with increasing Cu ratio.