Some semiconductors see their surfaces oxidize the moment they touch air, causing performance to drop sharply. A Korea-based research team developed a new surface treatment that reduces this problem and simultaneously improved the performance and stability of tin-based perovskite transistors.
A team led by Noh Yong-young in the Department of Chemical Engineering at Pohang University of Science and Technology POSTECH, working with researchers at Sungkyunkwan University and the University of Electronic Science and Technology of China, said on the 2nd that they found a way to overcome the limitations of tin-based perovskite semiconductors that are vulnerable to air. The findings were published the same day in the international journal "Nature."
A transistor is a tiny switch that turns electrical signals on and off. Tin-based perovskites were considered next-generation semiconductor materials because charges move well through them, but there was a problem: tin ions at the surface met air, created defects, and degraded performance.
The team developed a method to treat the surface of cesium–tin–iodine semiconductors with potassium acetate. Then the tin ions that had caused performance degradation turned into volatile species and disappeared, and a potassium iodide protective layer formed in their place.
As a result, unlike conventional devices whose performance declined within minutes in air, the new device operated stably for more than 4 hours. The threshold voltage required to turn on the device fell, and the device maintained its initial performance for over a month even at 100 degrees.
Noh said, "It will serve as a core technology across a broad range of future electronics industries, including vertically stacked DRAM memory devices for artificial intelligence (AI) computing, next-generation display driving circuits, wearable devices, and high-density semiconductor devices."
References
Nature (2026), DOI: https://doi.org/10.1038/s41586-026-10714-1