A domestic research team has developed an "ultrathin shield" that perfectly blocks electromagnetic waves inside thin and light semiconductors.
Professor Yeon Han-ul of the School of Materials Science and Engineering at Gwangju Institute of Science and Technology (GIST) and Professor Joo Young-chang of the Department of Materials Science and Engineering at Seoul National University said on the 30th that their team developed a high-performance, ultra-conformal electromagnetic interference (EMI) shielding film. The results were published the same day in the journal Nature. The study also involved Professor Kim Myung-gi of the Department of Energy Engineering at Korea University and researcher Lee Seong-su of the Korea Institute of Science and Technology (KIST).
An electromagnetic wave shield prevents external electromagnetic waves from causing semiconductor malfunctions. To make semiconductors lighter and smaller, the shield needs to be thinner, but to block waves, it needs to be thicker—a contradiction. Yeon said, "These two conditions were a physically conflicting dilemma," adding, "Our goal was to solve this challenge."
Until now, the common approach was to create fine pores inside the shield to scatter electromagnetic waves. But this method is difficult in semiconductor processes. Making pores requires high-temperature steps and is hard to control uniformly.
To solve the "thickness–performance dilemma" of existing shields, the team introduced a new composite film structure. The key is a sandwich structure that inserts the two-dimensional material "MXene" between metal thin films.
MXene is a two-dimensional nanomaterial with alternating layers of metal and carbon. It boasts excellent electrical conductivity and versatile chemical design, earning it the nickname "dream material." It is especially drawing attention as a next-generation ultrathin shielding material that blocks electromagnetic interference in the extremely high-frequency range.
With the metal–MXene sandwich structure, electromagnetic waves are reflected, scattered, and effectively absorbed inside. As a result, the team kept the shield thickness below 2 μm (micrometer, one-millionth of a meter) while boosting shielding performance by roughly 100 times over existing materials.
Even when the MXene film thickness was reduced from 1 μm to 200 nm (nanometer, one-billionth of a meter), performance barely changed. The team said the technology does not require high-temperature processing and can be implemented with existing spray coating and physical vapor deposition (PVD) used in semiconductor packaging, making it highly promising for commercialization.
Yeon said, "This study is like Columbus's egg." Christopher Columbus, the Italian explorer who discovered the Americas, stood an egg upright by cracking one end. Others failed because they tried to balance the egg in its original state. The point is that, while simple on the surface, the team solved the essence of the problem in a way no one had tried.
He said, "We implemented the simple idea of alternately stacking metal and MXene," adding, "It was difficult to place MXene uniformly on metal, but the research proceeded smoothly thanks to a surface treatment technique we developed." However, the cost of MXene, the key material, remains a hurdle for commercialization, as it is roughly more than 1,000 times more expensive than conventional metals. Yeon projected, "There is sufficient market potential in areas such as military electromagnetic devices and high-performance semiconductors."
Yeon joined GIST in Dec. 2021. He said, "My first goal was 'to publish my lab's first paper in Nature,'" adding, "Thanks to my Ph.D. advisor Professor Joo Young-chang and my postdoctoral mentor Professor Kim Ji-hwan at MIT, I was able to dream big."
References
Nature (2025), DOI: https://doi.org/10.1038/s41586-025-09699-0