KAGAKU KOGAKU RONBUNSHU, Vol.22, No.4, 786-793, 1996
Improvement in leveling of pulse-plated metal deposit
An electric potential field in an electrolytic bath that contains electrodes of various geometric shapes for pulse plating was numerically analyzed by using the finite element method, and dimensionless thickness distribution of metal deposit on the cathode was estimated from the potential distribution in the bath. Relations between the potential distribution in the bath and the thickness distribution of metal deposit were investigated on the basis of both calculated results and experimental data for pulse plating of copper. Moreover, an improvement in leveling of the pulse-plated metal deposit was discussed. The calculated results of dimensionless thickness distributions of metal deposit on the cathode agreed with the experimental ones, showing the validity of the numerical analysis employed in this work. Relations between the thickness distributions of metal deposit and the geometric factors such as distance between the electrodes, size and shape of the electrodes were quantitatively clarified by the present numerical analysis. Furthermore, by including cutoff plates near the cathode, the electric potential field in the bath could be controlled, and leveling of the pulse-plated metal deposit was also improved effectively.