Growth of Ultrathin Chemically-deposited CdS Films from Ammonia-thiourea Reaction System
Faculty of Computing, Health and Science
School of Engineering / Centre for Communications Engineering Research
Polycrystalline CdS films, with thicknesses typically 0.005 to 0.5 /spl mu/m, have been chemically deposited from an ammonia-thiourea system. The influence of reaction parameters (i.e. concentration of reactants and pH) on film growth rate were determined and modelled. The results of a kinetic study are presented, resulting in the formulation of a growth rate formula. The deposited film properties are dependent on temperature, stirring, relative concentrations of the solution reactants, type of reactants, and solution pH. Thin film growth is thermally activated with an activation energy E/sub A//spl sim/5/spl times/10/sup 23/ eV/mol.