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66 PCB007 MAGAZINE I SEPTEMBER 2018 planned application (TSV, RDL, pil- lars, bumps, filled through-holes), not to mention the optimum floo- ding and the best substrate agitati- on (Figure 12). The terms "strong," "weak," and "weak to strong," stand for any ad- ditive's relative magnitude of its accelerating, suppressing, levelling power. At the end of the day, it is not only the voltammetry/chronopo- tentiometry helping to design and qualify any particular chemistry for a given application/geometry/ tool, but exhaustive designed expe- riments regarding: • Chemistry/concentrations • Current density • Temperature • Tool selection • Tool auxiliaries Therefore, a one-fits-all bath composition may still be a mere vision. Typical electrochemical criteria for copperplating, in terms of acti- vity of the single components, are listed in Table 5. Copper Textures and Performance Out of the manifold of possib- le copper lattices, the configurati- on as being named 1,1,1—per Bra- vais classification/Miller Indices— has proven to be the most preferred when speaking in terms of hard- ness and elongation and therefore reliability (Figure 13). When flawlessly packed to each other, these basic bi-pyramidal cells build up to so-called nano-twinned columnar structures [1] being almost insensitive to the formation of Kir- kendall voids [2-6] in intermetalic sol- der layers. Figure 11: Leveller concentration and limiting current. Figure 12: Application-specific bath-type selection. Table 5: Dialing in the application.