ACFS Interconnection Technology for Wearable Electronics Packaging

ABSTRACT Due to increasing demand for higher performance, greater flexibility, smaller size, and lighter weight in mobile electronic products, there have been growing needs of wearable electronic products in near future. Wearable watches, glasses, wrist bands, shoes, and clothes have been recently introduced in the market. To realize wearable electronic products, there are four core electronic hardware technologies - (1)semiconductor, (2)display, (3)battery and (4)packaging & interconnection technologies. In the flexible semiconductor devices, much more development is needed in the future. And flexible displays are already available by introducing OLED (organic LED) realized on polymer films. And flexible batteries have been demonstrated by several companies already. In addition, in the flexible packaging & interconnection, current solder-based and socket-based interconnection methods have a limitation of bending and flexing. Therefore, new interconnection method has to be introduced to provide solution for flexible packaging & interconnection. For the realization of wearable electronics, In the electronic packaging technology for wearable electronics, flexible IC packaging & FOF (Flex On Flex) technologies using ACFs become important, because of ACF interconnection provides excellent electrical flexibility compared with solder- or socket-based interconnection methods. And CIF (Chip In Flex) assembly using ACFs shows excellent flexibility with electrical continuity at a static bending test of 4.5 mm bending radius. In addition, the common socket connectors in mobile electronic products can be successfully replaced by the solder ACF based FOF technology. In this presentation, it will be presented how the ACFs technology can be successfully used for the electronic packaging of wearable electronics.