According to experts, there are already more than 20 billion interconnected objects in use worldwide - more than a third of them are "smart" everyday objects that communicate and interact in the Internet of Things (IoT). One sticking point is the power supply: In order to operate for as long as possible, smart objects must be energy self-sufficient.
Possible solutions are demonstrated by the EU project EnSO (Energy for Smart Objects), which was completed at the end of 2020: 39 companies, universities and research institutes from eight countries, including researchers from Fraunhofer EMFT, have designed a novel electronics technology platform for robust and highly miniaturized energy supply modules for electronic systems. In addition, novel rechargeable microbatteries have been developed which can be recharged by energy from the environment, e.g. from temperature differences or sunlight.
As part of the project, Fraunhofer EMFT scientists have developed a novel chip-foil package for power management chips, a key component of micro-energy sources. In addition to its low overall height of less than 200 µm, it is also mechanically flexible, meaning that it can be bent to a certain extent. The connection contacts of the new package are fully compatible with conventional QFN-type chip packages.
The required manufacturing processes can also be carried out in a roll-to-roll process, so that a scale-up of production on EMFT's pilot facilities would be possible. In reliability tests, the new chip foil packages showed high resistance to mechanical and environmental stresses such as bending stress, rapid temperature changes and humidity.