Electronics should function reliably for as long as possible. However, implants that dissolve in the body after they have done their job would eliminate the need for patients to have another operation.
Electronic components that are completely broken down in a biological environment after a pre-defined operating life open up novel applications as well as ways for reducing their ecological footprint. One enabling technology for such components is the manufacture of biodegradable conductive traces on biodegradable substrates using vacuum technologies. This technology was developed by Fraunhofer FEP.
A novel application area for these innovative electronic components for example is in the field of active medical implants that after expiration of their operating life are resorbed by tissue, thereby sparing the patient a second surgical intervention.
Biodegradable electronics for active implants
The Fraunhofer Gesellschaft e. V. is now funding the “bioElektron – Biodegradable Electronics for Active Implants” project through its in-house program. The goal of the project is the development of essential components for biodegradable electronic parts that can be employed for example in an implant.
This includes in particular biodegradable
- conductor structures
- electrodes for collecting electrical signals or delivering electrical stimulation
- thin-film transistors and circuitry
- barrier coatings as moisture and gas barriers, and electrical insulation layers
These elements will be monolithically integrated into a flexible thin-film device.
Conductor structures and organic thin-film transistors are being developed at Fraunhofer FEP using vacuum technology. Deposition of magnesium via thermal evaporation under high vacuum conditions is being used as an enabling technology for this purpose. Magnesium is known for being a biodegradable and biologically compatible metal that is already employed in clinical environments as an absorbable implant material. The challenge consists of depositing this metal upon biodegradable polymer films that magnesium does not adhere sufficiently to under normal process control. By suitably pre-treating the substrates using a combination of drying, plasma treatment, and utilization of seed layers, finely structured high-quality conductor structures were able to be produced.