Projections expect up to 24 Billion connected devices worldwide by the year 2020 – more than a third of them will be “smart” devices of our everyday life, communicating and interacting in the Internet of Things (IoT). In this context, energy supply is known to be a critical point: The smart objects need to be energy self-sufficient in order to make the operating time as long as possible. Within the project “EnSO” (Energy for Smart Objects), 39 partners from eight countries cooperate to establish new solutions for an intelligent energy supply.
Within the project, Fraunhofer EMFT scientists will develop concepts and technologies for integrating and embedding electronic microchips into autonomous energy supply units. The height of the compact packages is expected to be far less than one millimeter. Furthermore, the packages shall be mechanically flexible, and thus adaptable to diverse ambient designs. To meet this specification, the Munich scientists plan to embed a very thin, flexible microchip into an ultra-flat foil-based housing. For bonding, diverse technological concepts will be probed: Besides Flip-Chip-solutions, where the chip is placed, bonded and embedded on the wiring foil face-down, also new technologies will be applied, where the chip is placed on a foil face-up and embedded with a casting compound. The bonding as well as the wiring level with external interconnections will be implemented by means of established processes of thin-film lithography.
While the first EnSO-demonstrator for an ultra-thin foil package will still be based on Flip-Chip technology, microchips with face-up configuration are expected to be used already in the next generation of foil packages.