Eco-designed Conformable Inorganic Electronics to Improve the End of Life of Smart Objects: Sensor Processing and Applications

We developing technologies that aim to add flexible electronics onto objects, researcher have to take into consideration environmental issues such as plastic pollution. Faced with this challenge, the development of technologies that comply with current standards such as WEEE (waste electric and electronic equipment) legislation is crucial. Green electronics based on fully biodegradable materials are under development but need time to be put on the market. Meanwhile, inorganic electronics remain a good candidate. Consequently, it makes sense to transfer inorganic electronics onto objects that can be dismantled and recovered. Here, an eco-designed technology allowing the transfer of electronics onto objects is detailed. Silicon-based devices are transferred from polyimide substrate (PI) to water-soluble substrate (PVA, poly­(vinyl alcohol)). It is highlighted that the transfer of inorganic layers from PI to PVA substrate does not have a negative impact on the device’s mechanical and electrical characteristics. To demonstrate such a concept, we have transferred strain gauges and temperature sensors onto daily life objects and achieved the same performance as sensors fabricated onto polyimide substrate. Moreover, materials transferred onto the object using PVA substrate can be dismantled and recovered at the end of object’s life, highlighting that hydrosoluble substrate is a good candidate for eco-designed technology.