Effects of annealing to the properties of copper oxide thin films deposited on different substrates by SILAR method

In this thesis, Cu2O (cuprite) semiconductor thin films were fabricated on glass (amorphous) and ITO (polycrystalline) substrates using SILAR (Sequential Ionic Layer Adsorption and Reaction) method at 60 oC for 36 immersion cycles. The produced Cu2O semiconductor thin films were subjected to thermal treatment (annealing) in a furnace at 160 oC, 260 oC, 360 oC and 460 oC in air atmosphere for one hour. The effect of annealing temperature on the structural, morphological and optical properties of the films was investigated. X-ray diffraction (XRD) analysis showed that Cu2O thin films grown on glass and ITO substrates grew in cubic phase and polycrystalline structure. It was also found that Cu2O thin films were completely transformed into CuO (tenorite) at annealing temperatures of 260 oC and above. CuO thin films were found to grow in monoclinic phase and polycrystalline structure. The basic optical parameters (%T, %A, %R, n, k, Ԑ1, Ԑ2, Eg) of the semiconductor films were calculated using data obtained from UV-vis spectrophotometry. The energy band gap (Eg) values of the thin films fabricated on glass and ITO substrates and annealed at different temperatures were found to be 2,13 – 1,76 eV and 2,11 – 1,70 eV, respectively. Field Emission-Scanning Electron Microscopy (FE-SEM) images show that the thin films have a homogeneous and spherical structure in general, and a tighter structure is formed with increasing annealing temperature.