The future of electronics holds the potential for even smaller and more efficient devices by packing more memory cells into a compact space. A promising approach to achieve this is incorporating the noble gas xenon during the production of digital memory. This method, revealed by researchers from Linköping University in a study published in Nature Communications, helps ensure a uniform coating of materials even in tiny crevices.
The future of electronics holds the potential for even smaller and more efficient devices by packing more memory cells into a compact space. A promising approach to achieve this is incorporating the noble gas xenon during the production of digital memory. This method, revealed by researchers from Linköping University in a study published in Nature Communications, helps ensure a uniform coating of materials even in tiny crevices.
Twenty-five years ago, a memory card for cameras could store 64 megabytes of data. Now, a memory card of the same size can hold 4 terabytes, which is over 60,000 times more capacity.
To create electronic storage, like a memory card, layers of electrically conductive and insulating materials are alternated in very thin sheets. Tiny holes are etched through these layers, which are then filled with a conductive substance using a technique that employs vapors of different materials to form these thin layers.
Memory cells are formed wherever the three different materials intersect within the holes, collectively creating digital memory. The more intersections there are, the greater the data storage capacity. Hence, increasing the number of layers and the fineness of the holes leads to more memory cells. However, this increases the challenges of filling the holes.
“The real challenge is getting the material inside the holes and ensuring an even coating on their interior surfaces. If there’s too much material at the hole’s opening, it can become blocked, preventing the rest of the hole from being filled. The atoms carried by the molecules must reach the very bottom,” explains Henrik Pedersen, a professor of inorganic chemistry at Linköping University.
To visualize this challenge, imagine trying to fill the world’s tallest building, the Burj Khalifa in Dubai, which stands at 828 meters. If we were to scale the holes to 100 nanometers in diameter and 10,000 nanometers deep, the base of the Burj Khalifa would only be eight meters wide.
What the researchers from Linköping University have done is incorporate the heavy noble gas xenon during the coating process, resulting in an even material thickness at both the top and bottom of a hole.
The usual method to achieve consistent thickness is by lowering temperatures, which slows down the chemical reactions. However, this can also lead to inferior material characteristics. By introducing xenon, the researchers could maintain sufficiently high temperatures to ensure excellent material quality.
“We’re still trying to understand the precise mechanism behind this. We suspect that the xenon gas helps ‘push’ the molecules down into the holes. This was an innovative suggestion from my doctoral student, Arun Haridas Choolakkal. He had reviewed foundational gas movement equations and proposed that this method could be effective. We then conducted several experiments to verify this hypothesis, and it was successful,” says Henrik Pedersen.
The researchers have patented their technique and sold the patent to a Finnish company, which is now pursuing patents in multiple countries.
“This approach helps keep the patent active, and the company has the means to further develop the technology. I believe this innovation holds great potential to become a standard in the industry,” adds Henrik Pedersen.
