Abstract

Two sets of CdS films, doped and undoped films by screen printing technique, were prepared and investigated by UV-Visible spectrophotometer. The undoped as-printed films showed high transmittance (90%) and lower reflectance (10%), while the films sintered at 400◦C and 600◦C showed less transmittance (60%) and little increase in reflectance (20%), the band gap energy of these films have decreased from 2.44 eV to 2.35 eV with an increase in the sintering temperature. The Doped films showed (70%) transmittance and reflectance of (20%) and increase in the band gap energy up to 3.45 eV. These results nominates the CdS films to be used as n-type window layer in solar cells. Other optical constants like refractive index (n), extinction coefficient value (K) and dielectric values have been calculated.