Design and Fabrication of Bendable Double-Layer RDL Metallization Based on FOWLP for In-Mold Flexible Hybrid Electronics (iFHE)

This is the authors' abstract. We don't add key points for this paper.

This study investigates the structural design and fabrication of double-layer redistribution layer (RDL) metallization for in-mold flexible hybrid electronics (iFHE) utilizing fan-out wafer-level packaging (FOWLP) techniques. Within the configuration of an iFHE, the position of the stressneutral plane is meticulously controlled to mitigate mechanical stress affecting the first-layer RDL. Furthermore, a three-dimensional corrugated RDL architecture is introduced to augment the pliability of the second-layer RDL. A crucial void issue when PDMS compression molding-an inherent challenge in the fabrication process-has been addressed through the use of excimer light and silane coupling agents for surface modification. Empirical results indicate that both the first- and second-layer RDLs demonstrate resilience to cyclic bending loads. This research contributes a novel methodology for interconnecting functional components in iFHE based on FOWLP, ensuring enhanced mechanical robustness and flexibility.