TEST CELLS FOR PLATING

摘要

Plating cells are employed to define the link between processing conditions and deposit properties and characteristics for electrodeposition. Process Parameters: Solution concentration Conductivity, pH Temperature Current density Voltage/potential Deposit Parameters: Composition/purity Thickness uniformity Smoothness, brightness Hardness, ductility, strength Grain size The electroplater needs a rapid and convenient test method to give a good, not necessarily precise, indication of this interaction and, in particular, to indicate any departure from perceived optimum process conditions and then provide the means of correcting that departure. A number of cells have been devised to give such a convenient link. They attempt to correlate the parameters of prime concern—composition and current density—with deposit thickness and thickness distribution. Figure 1 and Table I illustrate this choice. Some of the cells in Fig. 1 and Table I have very specific applications, e.g., D and K for chromium plating, where the throwing power (TP) is poor and the CrO_3:SO_4 catalyst ratio is critical. Two (B,F) have been adopted for wider use on account of their versatility.