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78 PCB007 MAGAZINE I NOVEMBER 2019 better than the cyanide-containing gold baths. The impact of the nickel type can be seen in Figure 33. The HP nickel performs similarly or better than the MP nickel despite the negative impact of the CN Au 1 result in Figure 29. Conclusions Many of the benefits of CNF Au are described in the introduction of this article. This article highlights how the test results were generated using a production simulation tool. In doing so, the results are more poignant to the field and industrial practice. One of the key items of interest is the stabil- ity of the CNF Au bath. This has been a major vexation to many cyanide-free development ef- forts of the past. This article has demonstrated that the performance over a lifetime measured in MTOs is stable, predictable, and controlla- ble. The indications are also that the CNF Au is a drop-in replacement for cyanide-containing immersion gold in existing ENIG setups. This process readiness has been demonstrated by the compatibility of the CNF Au bath with both HP nickel and MP nickel. Where possible, this article has shown sta- tistically that cyanide-free immersion gold can be a viable competitor to cyanide-containing immersion golds. The benchmarking demon- strated that no discernible differences could be found between the cyanide counterparts and the cyanide-free bath. It is also realistic to sug- gest that the compatibility of the CNF Au and the HP nickel is something to consider for the highest reliability ENIG production. PCB007 Acknowledgements Without the hard work of the chemists and material scientists in Berlin, this article could not have been done. References 1. R.C. Agarwala and V. Agarwala, "Electroless Alloy/ Composite Coatings: A Review," Sadhana, Volume 28, Is- sue 3–4, pp. 475–493, June 2003. 2. DVS Technical Committee/Working Group, "Techni- cal Bulletin DVS 2811 (Test Procedures for Wire Bonded Joints): Joining in Electronics and Precision Engineering," Translation of the German Issue, February 2017. This paper was first presented at SMTAI 2018 and pub- lished in the technical proceedings. Rick Nichols is a global product manager for surface finishing at Atotech Deutschland GmbH. Sandra Nelle is a product manager for surface finishing at Atotech Deutschland GmbH. Gustavo Ramos is global product director for selective finishing at Atotech Deutschland GmbH. Robert Spreemann is a development engineer for surface finishing at Atotech Deutschland GmbH. Figure 32: ANOVA, analysis of the solder spread value of the types of gold bath. Figure 33: The impact of ageing on the solderability of the nickel types.

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