A team of scientists has developed a simple new way to protect a promising semiconductor material from one of its biggest enemies: air.
Their breakthrough could help create faster, more energy-efficient electronic devices in the future, including AI memory chips, flexible displays, wearable electronics, and advanced computer components.
The research was led by Professor Yong-Young Noh and his team at POSTECH (Pohang University of Science and Technology) in South Korea, working with researchers from Sungkyunkwan University and the University of Electronic Science and Technology of China.
Their findings were published in the journal Nature.
Modern electronic devices, including smartphones, rely on billions of tiny components called transistors.
A transistor acts like an electrical switch, turning electric current on and off. There are two main types of transistors.
N-type transistors carry electrons, while p-type transistors carry “holes,” which are empty spaces left behind when electrons move. Both types are needed to build fast and energy-efficient computer chips.
However, improving p-type transistors has been a major challenge for many years. Scientists have been searching for better materials that can make these transistors faster and more reliable.
One promising material is a tin-based perovskite called cesium tin iodide (CsSnI3). This material allows holes to move very quickly, giving it performance similar to some of today’s best semiconductor materials used in high-performance displays and memory chips.
Unfortunately, tin-based perovskites have one serious weakness. As soon as they are exposed to air, leftover tin ions on the surface react with oxygen. This chemical reaction creates tiny defects that block the flow of electricity. As a result, the transistor’s performance quickly drops, sometimes within just a few minutes.
To solve this problem, the researchers developed a new treatment called “Volatile Surface Reconstruction.”
The team coated the semiconductor with a chemical called potassium acetate. This treatment changed the unwanted tin ions into tin acetate, a compound that easily evaporates away. Once these harmful tin ions disappeared, another useful compound, potassium iodide, naturally formed in their place.
This new layer acts like a protective shield, covering the surface and helping prevent future damage from air. In other words, the process removes the harmful material while automatically creating a protective coating at the same time.
The results were impressive. The treated transistors needed less voltage to turn on, making them more energy efficient. They also achieved excellent hole mobility, meaning electrical charges could move through the material very quickly. In addition, the devices showed an extremely high on/off current ratio of more than 100 million, placing them among the best p-type perovskite transistors reported so far.
Perhaps the biggest improvement was durability. While untreated devices often stopped working after only a few minutes in open air, the new transistors remained stable for more than four hours. They also kept their original performance for over a month during accelerated aging tests at 100°C, showing excellent resistance to heat.
The researchers believe this new protection method could make tin-based perovskite semiconductors much more practical for real-world manufacturing.
In the future, the technology could support advanced AI memory chips, vertically stacked DRAM, next-generation display circuits, wearable electronics, and many other powerful semiconductor devices.
Source: KSR.
