Hybrid Systems‐in‐Foil

Abstract

Hybrid Systems-in-Foil (HySiF) is a branch of flexible electronics, which describes the fabrication process and design rules for integrating electronic components into polymeric foil. HySiF serves as a platform that complements the merits of the very large scale integration (VLSI) of silicon ICs with the large-area electronics resulting in mechanically flexible smart sensor systems. Here, a system-level concept for HySiF is discussed. Emerging applications, e.g. next generation smart labels, electronic skin with embedded AI and implanted devices that benefit from the HySiF concept are presented with many use-cases from industry and academia. Next, the HySiF concept is viewed from technology and manufacturing point of view, where challenges regarding substrate and interconnect materials are considered. The rise of ultrathin electronics, with focus on Flex-PCB and wafer-based processes, is reviewed. Common challenges that are facing during the integration of electronic components from different material systems, e.g. surface roughness, process-induced stressors, and assembly errors, are examined. Further, several active and passive electronic components that are found in the HySiF concept are reviewed. System-circuit-device or -sensor codesign is crucial for such complex systems-in-foil. Finally, a quick review for existing HySiF testing mechanisms is presented in order for the reader to estimate the effort required for developing complete hybrid flexible electronic systems.