Regresar

Densification kinetics of cds thin films annealed at low temperature

Abstract:

A systematic study of growth, annealing, and characterization of cadmium sulfide (CdS) thin films obtained by chemical bath deposition is presented. The aim of this work is to elucidate the densification kinetics and the annealing effect on microstructure, optical behavior, and band gap of annealed CdS films in the temperature range of 373.15-523.15 K, using nitrogen atmosphere. Film characterizations were performed by profilometry, X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy techniques. Additionally, optical properties and band gap of films were determined by UV-visible spectroscopy. CdS films intended for solar cell applications grown to an average thickness of 118 nm, exhibited band gap values in the range of 2.38 eV to 2.45 eV. Lastly, annealing process allows a densification degree increase up to 64 % and the kinetic study reveals that the densification process of CdS obeys to fractional order rate law with activation energy of 43.09 Kcal/mol.