Progress towards modelling the CdS chemical bath deposition process

Progress is reported towards the development of a comprehensive model usefu l in process design and optimisation of CdS thin-film growth. Model equatio ns are developed for the temporal variation of reactants concentrations as well as of the precipitating solid phase, both in the bulk and on the subst rate. A combination of possible elementary mechanisms is employed and the r esulting system of equations is solved numerically. Computational results s how that the model is consistent with available experimental data, on film thickness evolution, suggesting that it may prove very useful for optimisin g the CBD process with respect to its design variables. To conclude the pre sentation, some aspects of the deposit morphology at the early stages of it s growth are discussed. It appears that these first stages determine the pr operties of the final film. (C) 2001 Elsevier Science B.V. All rights reser ved.