With its proprietary and patented Supersonic Cluster Beam Implantation (SCBI) technology WISE can produce stretchable conductive materials on arbitrarily thin and soft substrates.
SCBI consists in embedding metal nanoparticles inside a preformed polymer base in order to form a conductive metal-polymer nanocomposite layer below its surface.
The electrically neutral nanoparticles are produced in the form of a supersonic beam and are shot at a high velocity toward the polymer base. Thanks to their inertia, the nanoparticles are implanted inside the polymer as bullets fired at a soft target, forming a conductive nanocomposite layer.
WISE’s SCBI allows to produce electrodes that are strongly attached to the polymer and are stretchable, flexible, biocompatible [medical grade] and allow a very effective stimulation. Furthermore, SCBI allows to embed electronic circuits in foils as thin as a few microns without damaging the foil itself.
The SCBI technology has been protected by patents in Europe, USA, Israel, Canada, India, Japan and Korea.
The SCBI technology allows to produce conductive systems that can sustain very large deformations, such as bending and stretching, and that do not deteriorate upon thousands of extensive repeated elongations.
WISE is therefore capable of producing stretchable electronics, i.e. electronic systems that can be arbitrarily shaped, bent or stretched, while remaining conductive and without losing functionality.
By placing adequate masks over the substrate during the SCBI process, it is possible to pattern the conductive layer with micrometric resolution, thus producing a multitude of conductive wires, micro-electrodes or complex circuits. The micro-patterning can be obtained also using rigid reusable masks that are not in contact with the substrate, thus avoiding the use of chemicals that could affect the biocompatibility of the device.
During the SCBI metallization process, the polymer is subjected neither to heating nor to electrical charging. This allows to metallize any polymer, without inducing its carbonization. The polymers can be in general used “as received” without the need for any chemical treatment, either before or after the SCBI process. The metals used for the electrodes are Platinum and Iridium, the standard materials for medical implants. The patterning does not require the use of any photolithographic step.
As a consequence, the biocompatibility of the pristine polymer used for the metallization is not altered neither during the metallization process, nor because of pre- or post- treatments. In-vitro biological tests have demonstrated the absence of cytotoxic effects directly or indirectly caused by the metallization process. These results are confirmed by in-vivo tests on animal models.
Thanks to the high roughness of their surface, the electrodes produced with the SCBI technology exhibit a very high surface area.
As a consequence, WISE’s electrodes have a higher efficiency both for stimulation and for recording than products on the market, as shown by electrochemical testing. In particular, the low impedance at low stimulation frequencies and the very small polarization of WISE’s electrodes pave the way to lower IPGs’ battery consumption and better and more efficient stimulation.