Elastic and conformable electronic circuits and assemblies using MID in polymer

For user comfort reasons, electronic circuits for implantation in the human body or for use as smart clothes should ideally be soft, stretchable and elastic. In this contribution the initial results of an MID (Moulded Interconnect Device) technology will be presented, showing the feasibility of functional stretchable electronic circuits. In the developed technology rigid or flexible standard components are interconnected by meander shaped electroplated metallic wires and embedded by molding in a stretchable substrate polymer, like silicone rubber or polyurethane. The meander design was supported by mechanical simulations in order to minimize the stress in the metal during deformation. In this way reliable stretchability of the circuits above 100% has been demonstrated. A simple stretchable thermometer circuit with 4 components embedded in Dow Coming Silastic (R) PDMS silicone material has been built and proper operation has been demonstrated.