The main research motivation is to increase the range of medical devices and capabilities to enable healthcare with better and new diagnostic & therapeutic procedures. Various medical and engineering aspects such as biocompatibility, medical device integration, reliability, smart materials, sensing, miniaturisation, microelectronics/ MEMS interconnection and packaging, and wireless powering & communication is involved.
Wearable, minimum invasive and implantable applications are considered, each type having its own challenges. For wearable applications, flexible/stretchable e-skin technology can be used which involves metallisation of very thin polymer layers.Minimal invasive applications are focused on miniaturisation and tubular integration as is for instance required for cardiovascular catheter sensing or smart hydrogel delivery. But other applications investigated include a diagnostic capsule for the gastro-intestinal tract and a nasogastric feeding tube.
For implantable devices inductive powering or energy harvesting and wireless communication play an important role. And also long-term reliability is very important requiring hermetic or non-hermetic solutions to withstand moisture ingress and mechanical stresses over a prolonged period of time.
One common technology platform between the various biomedical microsystems is the integration of a thin flexible circuit which can conform to a 3D medical device shape and could be protected with a polymer type coating. Thermoplastic biocompatible materials such as Polyimide and Parylene C are suitable substrate materials and circuitry and devices such as electrodes can be directly deposited on them. For attachment of sensors, IC’s, wires and other components, a “flip chip” interconnection method can be used. In combination with thinned devices and small size particles containing adhesives, low height profiles can be achieved which could enable a flat assembly for instance to be transformed in a rolled up tube.