Determination of structural and optical parameters of CuO thin films prepared by double dip technique

Cupric oxide (CuO) thin films are deposited on glass substrates by double dip method at various molar concentrations of copper sulphate salt. Growth mechanism is derived using oxolation process. The structural studies revealed the deposited films exhibited polycrystalline nature with monoclinic structure. The change in the molar concentration of copper sulphate salt has pronounced effect on the microstructural properties of deposited thin films. XPS and EDS spectra confirm the presence of Cu and O. Micro Raman spectra shows two A_g and B_g active Raman mode peaks corresponding to CuO phase. Deposited films showed a high absorbance in the visible range with the bandgap value of 1.3 eV making it a suitable material as semiconductor tandem absorber for solar cells. Optical constants such as refractive index (n), extinction coefficient (k), optical conductivity (σ) and dielectric constants (ε) were evaluated using an approximation protocol developed from well recognized procedures using the data obtained from UV spectroscopic technique. The prepared CuO thin films are identified as suitable candidates for optoelectronic devices and solar cell fabrication.