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68 PCB007 MAGAZINE I AUGUST 2019 and elongation for the fresh and aged bath. As shown in Figure 13, the tensile strength and elongation % for Process II passes the IPC Class III requirements of tensile strength great- er than 36,000 psi and elongation greater than 18%. Conclusions Two innovative processes for acid copper metallization in IC substrates were presented. The objective was to achieve planar via fill and flat profiles for fine-line applications and for higher uniformity of embedded trench designs between the pad height and fine-line height. The formulations reported here showed excel - lent via fill capability and fine-line profile %. Excellent uniformity between the pad and fine- line areas was obtained. The deposits produced by these formulations were shown to have low internal stress, both plated and annealed. The physical property of tensile strength and elon - gation produced by these deposits was stable as the bath aged and passed IPC Class III. A com- bined summary of these is shown in Table 3. All of the additive components utilized in these processes can be analyzed with common ana- lytical tools used in the industry. PCB007 References 1. T. Braun, K.-F. Becker, S. Voges, J. Bauer, R. Kahle, V. Bader, T. Thomas, R. Aschenbrenner, and K.-D. Lang, "24"×18" Fan-Out Panel-Level Packaging," IEEE/ECTC Pro- ceedings, 2014, pp. 940–946. 2. T. Braun, K.-F. Becker, M. Wöhrmann, M. Töpper, L. Böttcher, R. Aschenbrenner, and K.-D. Lang, "Trends in Fan-Out Wafer and Panel-Level Packaging," International Conference on Electronics Packaging (ICEP), Yamagata, 2017, pp. 325–327. 3. P. Broekman, A. Fluegel, C. Emnet, M. Arnold, C. Roeger-Goepfert, A. Wagner, N.T.M. Hai, and D. Mayer, "Classification of Suppressor Additives Based on Syner- gistic and Antagonistic Ensemble Effects," Electrochimi- ca Acta, Volume 56, Issue 13, May 1, 2011, pp. 4,724–4,734. 4. K.B. Herbert, S. Adhikari, and J.E. Houser, "Chemical Mechanism of Suppression of Copper Electrodeposition by Poly (Ethylene Glycol)," Journal of the Electrochemical Society, 152 (5), C324–C329, 2005. 5. S. Dharmarathna, I. Li, M. Sy, E. Zeng, B. Wei, W. Bow- erman, and K. Feng, "High-Throw DC Acid Copper Formu- lation for Vertical Continuous Electroplating Processes," IPC APEX EXPO 2017, February 14 –16, 2017. Figure 13: Physical properties, tensile strength, and elongation of Process II fresh and aged baths. Table 3: Comparison of the tensile strength and elonga- tion % of the via filling focused Process I and the embed- ded trench focused Process II, fresh vs. aged 50 Ah/L.