Firewall Design for High Quality Electroplating Redistribution Layers on 600mm Panel

Abstract

The quality of redistribution layer (RDL) dominates the electrical performance of semiconductor package. Theoretically, the RDL thickness uniformity control becomes more challenge as increasing the substrate size, especially on the 600mm panel platform. In this study, the dummy pattern around and across the panel, called as firewall, have been used to influence the electrical distribution, to overcome the electroplating copper thickness uniformity problem around the blank area, which is used to develop the high-quality fan-out panel level packaging (FOPLP). The experiment results show the RDL thickness non-uniformity can be improved by 21% and 30% by tuning the area and the metal density of firewall, respectively. This firewall tuning technology is useful to diminish the RDL thickness difference among all dies within the panel, which can be adopted in any high-performance large size panel level packaging.