Investigation of the physical properties of Cu2O thin films deposited on various substrates

The aim of this thesis is to deposit Cu2O (cuprite) semiconductor thin films on glass (amorphous) and FTO (polycrystalline) substrates using the SILAR method at different temperatures (30 oC and 70 oC) and with varying numbers of dipping cycles (10, 20, and 40), and to investigate the effects of these parameters on the physical properties of the films.The effects of substrate type, number of dipping cycles, and deposition temperature on the structural, morphological, and optical properties of the films were investigated. XRD analyses revealed that the Cu2O thin films grown on both glass and FTO substrates exhibited a cubic phase and polycrystalline structure. The fundamental optical parameters of the produced semiconductor films transmittance (%T), absorbance (A), reflectance (%R), refractive index (n), extinction coefficient (k), real and imaginary parts of the dielectric constant (Ԑ1, Ԑ2), and optical band gap energy (Eg) were calculated using the data obtained from UV-vis spectrophotometry. The Eg values of the films on glass substrates were found to be in the range of 1,98–2,39 eV at 30 oC and 1,88–2,45 eV at 70 oC. For the films on FTO substrates, the values ranged between 2,19–2,47 eV at 30 oC and 2,20–2,42 eV at 70 oC. Field Emission Scanning Electron Microscopy (FE-SEM) images revealed that the films generally had a homogeneous morphology and occasionally exhibited rod-like and spherical structures. It was observed that increasing the number of dipping cycles and the deposition temperature led to the formation of a denser and more compact structure.