Chapter Technical Meeting: Challenges and Opportunities in Shrinking RDL Features: Microstructure Control of Copper Deposits for Improved Fill and Reliability

Advanced Materials are key enablers of new Advanced Packaging & Interconnect Technology Architectures, particularly in FO-WLP (Wafer-Level Fan-Out Packaging). Circuit miniaturization and densification hinges upon extending thermomechanical and feature fill capabilities of Copper Chemistries. We will highlight the renewed focus of plating chemistry suppliers on revamping their RDL products to increase fill uniformity over large ranges in feature shape and size.

We will focus on limitations of traditional plating additive-based approaches and emerging feature fill approaches that extend via fill to aspect ratios below 0.1, then the mechanical challenges that arise from finer L/S dimensions and the opportunities to improve reliability performance. We will review the debate over re-engineering copper microstructure and provide new approaches to mechanical integration.

Finally, we will demonstrate how adjacent challenges in seed etching and PR resolution limits can be addressed in the medium-term by exploiting highly tailored copper deposits that enable unparalleled control over line shape during plating.

Speaker: Alejo Lifschitz Arribio, Senior Scientist, Dupont