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90 PCB007 MAGAZINE I NOVEMBER 2018 ure occurs during the subsequent soldering op- erations. Summary An innovative DC acid copper process for si- multaneously filling vias and plating THs was studied in a wide variety of conditions to col- lect information on its capabilities. The throw- ing power can be enhanced with optimized physical and chemical plating parameters while keeping very good via fill across a wide range of geometries. A high-copper, low-acid solution was used for TH ARs up to 5:1 in 0.8-mm panels. The optimization included organic additive concen- trations and plating parameters. Conditions of minimum and maximum throwing power and dimple size were determined, and experiments were run under these conditions. A compro- mise was achieved between plating conditions that favor via fill and those that are beneficial for TH plating. For thicker panels of 1.6 mm, a TP min = 78% was obtained for 0.25-mm diameter holes and AR = 6.4:1 in a bath containing reduced copper ions concentration and increased acid concentration. Insoluble and soluble anode ap- plications were shown in this article. Filling through-via-holes in core layers of HDI of the PCB and IC package substrate was discussed. X-through vias, 90 x 150 mm that were filled with <5 microns or zero dimple and no voids or defects were shown. The fill- ing conditions are given. Further work is un- derway to achieve filling up through-via-holes in thicker cores. For mechanical properties, tensile strength >42,000 psi and elongation >20%, as well as the thermal resistance of copper deposited from baths with soluble or insoluble anodes, met and exceeded industry standards thus sat- isfying the need of a highly reliable copper electroplating process. PCB007 This paper was originally presented at IPC APEX EXPO 2018 and is published in the pro- ceedings. References 1. C.F. Coombs, Jr. (2001). Coombs' Printed Circuits Handbook: Fifth Edition. McGraw-Hill. 2. V.M. Dubin (January 1998). "Copper Plating Techniques for ULSI Metallization," Advanced Metallization and Interconnect Systems for ULSI Application in 1997." Materials Research So- ciety Symposium Proceedings, pp. 405–411. 3. J. Horkans & J.O. Dukovic with P.C. Andricacos, J.L. Stick- ney, P.C. Searson, C. Reidsema-Simson, & G.M. Olezek (Eds.) (2000). "Electrochemical Processing in ULSI Fabrication III." ECS Proceedings, 8, p. 103. 4. E.K. Yung (1989). "Plating of Copper into Through-Holes and Vias." Journal of the Electrochemical Society, 136, pp. 206–215. 5. J.J. Kelly, C. Tian, & A.C. West (1999). "Electrochemi- cal and Fill Studies of a Multicomponent Additive Package for Copper Deposition." Journal of the Electrochemical Society, 146, p. 2540. 6. M. Schlesinger & M. Paunovic (2010). Modern Electroplat- ing: Fifth Edition. John Wiley & Sons Inc. 7. J.P. Healy, D. Pletcher, & M. Goodenouth (1992). "The Chem- istry of Additives in an Acid Copper Electroplating Bath: Part III." Journal of Electroanalytical Chemistry, 338, p. 179. 8. T. Pearson (2005). "Transactions of the Institute of Met- al Finishing." The International Journal of Surface Engineering and Coatings, 83(4), pp. 171–180. 9. M. Nikolova, C. Rodriguez, K. Feng, W. Bowerman, & J. Wat- kowski (2017). "Innovative Acid Copper Process for Simulta- neously Filling Vias and Plating Through Holes." Proceedings SMTA International, pp. 882–890. The threat of cyber-attacks is no longer theoreti- cal. Cybersecurity researchers, often referred to as "white hat hackers" have identified device vulnerabili- ties in non-clinical, research-based settings. They've shown how bad actors could gain the capability to exploit weaknesses, thereby acquiring access and control of medical devices. The FDA isn't aware of any The FDA's Mission to Protect Medical Devices from Cyber-attacks reports of an unauthorized user exploiting a cyberse- curity vulnerability in a medical device that is in use by a patient; however, the risk of such an attack per- sists. The FDA is working hard to be prepared and re- sponsive when medical device cyber vulnerabilities are identified. (source: PR Newswire)

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