Fabrication and Characterization of an n-CdO/p-Si Solar Cell by Thermal Evaporation in a Vacuum

A CdO/Si solar cell was fabricated via deposition of a CdO thin film on p-type silicon substrate at room temperature by thermal evaporation technique for CdO powder in a vacuum (similar to 2.2 x 10(-5) mbar). The synthesized thin film has a thickness of approximately 346 nm. Scanning electron microscopy revealed that the thin film had a good quality structure. X-ray diffraction and energy dispersive X-ray analysis were used to characterize the structural properties of the solar cell. The CdO thin film had a grain size of 34 nm. The solar cell yielded a minimum effective reflectance that exhibited excellent light-trapping at wavelengths ranging from 400 nm to 1000 nm. Photoluminescence spectroscopy was conducted to investigate the optical properties. The direct band gap energy of the CdO thin film was 2.46 eV. The photovoltaic properties of the CdO/Si solar cell were examined under 100 mW/cm(2) solar radiation. The cell had an open circuit voltage (V-oc) of 460 mV, a short-circuit current density (J(sc)) of 18.8 mA/cm(2), a fill factor (FF) of 0.685, and a conversion efficiency (eta) of 5.92%.