Researchers from New York University (NYU) Tandon School of Engineering have created a new type of composite film capable of blocking electromagnetic interference (EMI). The new technique is both low-cost and extremely effective. Electromagnetic interference can have disastrous effects on a host of devices, including smartphones, drones, aircraft, and medical devices. Scientists have been looking for new, improved ways to protect people and technology — and this film is the latest innovation.
To construct this high-tech composite film, scientists used spin-spray layer-by-layer processing. This involves placing spray heads above a spin coaster. The heads rain down sequential, nanometer-thick monolayers of oppositely-charged compounds. The end result is a high-quality film that can be attached to any component. This method has the added benefit of being far more time-efficient than previous methods for making film.
This technology means that scientists can quickly and effectively make film that is flexible, semi-transparent, and most of all EMI-shielding. The film is made up of hundreds of alternating layers of carbon nanotube, polyelectrolytes, and an oppositely charged titanium carbide known as MXene. MXene is an important addition to the system, as it can adhere to any surface, making it extremely versatile. It’s also conductive — which helps enormously in the fight against EMI.
The new system grants scientists exhaustively detailed control over the design of the film. Developers can make nanometer-small adjustments to conductivity and transparency with relative ease. The high conductivity of the film allows it to weaken and disperse an EMI pulse, ultimately blocking it while still allowing light to emanate through.
This technology is also easier and faster to fabricate than previous versions — which is of significant interest to manufacturers. While the old dip coating method took days to complete, the new method can create hundreds of layers of film in mere minutes.
Unfortunately, spin-spraying does have one significant drawback: the method limits the size of the components that can be used. However, scientists are confident that the method can easily create EMI shielding for items that have the same diameter to 12-inch wafers. This means this method could be used in current manufacturing of semiconductors.
Scientists are working to expand the size limits of the spin-spraying technique, and hope to make the process even faster and more effective. Commercialization of this technology will be the next step in the process.
