Optical and structural properties of CdS films grown by CSVT technique

CdS films were grown on glass substrates by the close spaced vapor transport technique (CSVT). We deposited two series of samples: a) with a substrate temperature of 150°C (group A) and b) with a variation of substrate temperature between 200°C and 550°C, at intervals of 50°C (group B). The samples of group A were annealed in N₂ atmosphere, from 200°C to 400°C, at intervals of 50°C. All samples were measured by X-ray diffraction and optical transmission. X-ray diffraction patterns show that the films had a mixture of cubic and hexagonal structure remained unchanged after the thermal annealing, the main phase present was cubic. The energy band gap shows a thermal stability. The substrate temperature has no effect over the crystal structure and band gap energy. Transmittance and X-ray measurements show a thermal stability of the crystal structure and band gap energy.