The new developed chemistry by Dow Chemical was able to make filled via with thinner surface deposition than conventional product. In addition, it showed not only satisfied via-filling ratio as well as conventional chemistry but also narrower deposition thickness range than conventional product. The bottom-up in via hole was observed even 4 um deposition thickness on the surface with new chemistry. The via hole was almost filled by deposited copper in 6 um condition. Then, the new chemistry showed satisfied via-filling shape even 9 um condition. In terms of inorganic composition, the new chemistry is formulated with lower concentration of copper and higher acid in virgin make up solution compared with conventional chemistry. It can contribute avoiding void issue for reliable electrical connection. Solder float test was performed per IPC-TM650 2.6.8 as thermal shock resistance test to verify thermal reliability of plated vias on pattern board. No crack or any defect was not observed on copper filled vias after the thermal shock.
Productronica innovation award 2015: Halle B1, Stand 305