Site-Specific Measurement of Cathodic Pulse Shape and Plating Current Density for Optimization of Pulse Plating Lines

摘要

Two important aspects concerning optimum performance of a (reverse) pulse plating line are (ⅰ) the uniform and correct pulse shapes anywhere on the PCB and (ⅱ) the uniformity of the plating current density (thickness distribution) over the whole plating window of a vertical line or the entire width of a PCB in a horizontal line. To measure both precisely, comfortably, and quickly the island method was enhanced to Optipulse 80. Special test boards with measurement islands and calibrated shunts on both sides are used to check site-specifically the cathodic plating current density as close as possible to production conditions. Sampling frequencies up to 20 kHz precisely resolve pulses as short as 0.5 ms. Up to 80 channels are sufficient to obtain a well resolved overview over the plating window of most vertical lines within less than ten minutes. Statistical data evaluation and visualization features make this a powerful tool for optimization of pulse plating lines (also applicable to DC plating, of course). The system now has been successfully in use for more than three years. This paper presents a short review of its history and the actual features as well as some examples from recent data.