Multi-Stepped Solder Resist Patterning Technology for Advanced Packaging

This paper introduces a novel process technology of solder resist (SR) thinning, RT system, to form multi-stepped structures. The study explores the demonstration of complex SR structures, such as SR dams with partial Cu pad exposure, and different types of SR opening structures in a single SR layer. Analysis and demonstration in this study indicates that the technology offers a unique and reliable process solution for the next generation of integrated circuit (IC) packaging industry.