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80 PCB007 MAGAZINE I JANUARY 2024 Electrodeposition comes down to funda- mentals. In the early days of plating, many users considered the nuances of metallization as black magic. ose days are long gone. Hav- ing a thorough understanding of the critical parameters that influence electrodeposition will determine success. Key Process Considerations Everything is a process, and the electrode- position of copper is no exception. Critical to the success of any process is the control of key parameters that influence the plating process. e second consideration is the fundamentals. is month's column will look at some of these fundamentals—and for good reason because much has changed over the past several years. ese changes include the technology of the circuit board—smaller vias and thicker boards. Whenever you make a via smaller, and you add more layers (and make the boards thicker), there is an increase in the ohmic resistance through the via. e greater the resistance, the more difficult it is to get an even distribution of plated copper through the vias. With Ohm's Law, V = IR, you apply a voltage to a plating tank. If you have a 10:1 aspect ratio board and a 20:1 aspect ratio board, which one will be more difficult to plate? It's very sim- ple: the 20:1 board. is is because the resis- tance increases significantly down through the hole. From a technology standpoint, you must make several adjustments, which the indus- try has done. We've seen adjustments in tank design, plating rack handle design, process control, and the formulation of new additives that enhance throwing power and overall plat- ing distribution. Electrodeposition of Copper, Part 6 Trouble in Your Tank by Michael Carano, IPC CONSULTANT