Synthesis of CdTe nanoparticles by PVD Technique and Study their Physical Properties

Abstract

Nano-crystalline CdTe films were coated on a glass substrate by vacuum evaporation (PVD) technique, with the annealed temperature at (25, 100, 150, and 200 °C). The samples were examined by Uv‒visible instrument to investigate the transmittance and absorption. The dependency of the absorption coefficient (α) on the wavelength has been investigated. The X-ray diffraction revealed that cubic crystalline was obtained and the peak intensity increased as the temperature increased. The crystallite size increased during grans growth when annealed temperature increased. The estimated energy gaps of the CdTe films were 1.86, 1.87, 1.85, and 1.84 eV, due to the differences in particle sizes. Electrical characteristics have been made to detect the resistivity and conductivity and it was found that the resistivity changes directly with the increase of the energy gap and inversely with the increase in the conductivity of the CdTe films. The surface morphology was homogenous and very smooth surfaces were detected.