Preparation and optical characterization of chemical bath deposited CdCoS2 thin films

Abstract

Thin film of CdCoS2 was deposited on glass slide from aqueous solutions of CoCl2.6H2O, CdCl2.2 1/2H2O and thiourea in which ammonium solution and TEA were employed as complexing agents. The film was studied for its optical properties using spectrophotometers. The optical characterization show that the band gap range between 2.50 and 2.70 eV which is between the band gap of CoS and CdS but very close to that of CdS which shows that the film is rich in cadmium. The film was found to have an average transmittance of greater than 55% in the VIS-NIR regions and exhibit average reflectance of greater than 11% in the same regions. Other optical parameters such as refractive index, extinction coefficient, real and imaginary dielectric constants and optical conductivities were also estimated. The film exhibits poor transmittance in the UV regions, hence, they could be effective as coatings for poultry houses and as well good materials for solar cell fabrication. © 2006 Asian Network for Scientific Information.