INFLUENCE OF DOPANT CONCENTRATION ON THE STRUCTURAL AND OPTICAL PROPERTIES OF NANOCRYSTALLINE ZnS:In FILMS

ZnS and ZnS:In films containing three different rates of In were produced on glass subtrates heated up to 300 +/- 5 degrees C. Structural analyses of the films were done by X-ray diffraction (XRD), Raman and Infrared (FT-IR) spectroscopies. It was determined that the films obtained by ultrasonic spray pyrolysis (USP) method had polycrystalline structure. All observed XRD peaks belong to hexagonal wurtzite ZnS structure. Crystallite sizes of the films were approximately calculated in 4.61-4.63 nm range. SEM images showed that particles have homogeneously distributed and held onto surface. It was observed from the EDS results that the In rate of films increased by increasing In doping in the solution. FTIR spectra revealed presence of four significant peaks. Peak observed around 930 cm(-1) corresponded to the Zn-S vibration while, smaller peaks around 3500 cm(-1) corresponded to the -OH group of H2O stretching. The aromatic ring C-H bending vibrations gave the peaks around 750 cm(-1) . The optical properties of ZnS and ZnS: In films were investigated by optical transmittance and reflectance spectra.