A diffusion model was developed to calculate the rate of deposition of metals by a periodically pulsed current. The results indicate that although the magnitude of the instantaneous applied current for deposition can be considerably higher than that of direct current plating under suitable conditions, the limiting over‐all plating rate was in general lower. Experimental confirmation was established using the phosphate, citrate, and cyanide gold solutions. The diffusion coefficient of the complexed gold cyanide ion false(normalAufalse(CN)2−false) was measured. The values were 1.63×10−5 cm2/sec,1.67×10−5 cm2/sec , and 1.68×10−5 cm2/sec at 60°C for the phosphate, citrate, and cyanide solutions, respectively. The pH value, specific conductance, and kinematic viscosity of these solutions were also measured and tabulated. The rate of chemical dissolution of gold in the cyanide solution was also investigated.

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A model has been developed to predict current distribution in electrodeposition onto substrates that contain lithographic patterns. The aim of the work was to understand the strong effects that substrate patterning can exert on the thickness distribution of plated films. Based on the familiar potential-theory model for secondary current distribution in electrochemical cells, the model is applicable at length scales that are large compared to the individual features of a pattern. The pattern is described entirely as a continuous distribution of"active-area density," a property that reflects any relative change in the electroactive area of the substrate due to the pattern. The active-area density enters the expression that relates the surface overpotential to the current density. An implementation of the model, using the boundary-element method, has been applied to several problems that illustrate the effects of substrate patterning on current distribution. For each example, the dimensionless groups that characterize the current distribution have been identified, general solutions have been obtained over wide parameter ranges, and behavioral trends have been interpreted.

A Nernst diffusion model was employed to obtain an analytical expression for the transient current response of a reversible deposition reaction with insoluble product occurring on a rotating disk electrode under linear potential sweep conditions. The results indicated that for low sweep rates the current increases monotonically with time. However, at high sweep rates a maximum value for the current density at finite values of time is predicted. The peak current density normalized with respect to the diffusion limiting current density was found to be a linear function of the square root of a dimensionless sweep rate. Furthermore, in this region the response of a rotating disk electrode is the same as that in a stagnant system. An experimental investigation based on the reversible deposition of silver showed good agreement with the theoretical predictions.