Researchers at University of Pennsylvania demonstrated memory technology capable of enduring temperatures as high as 600\u00b0 Celsius\u2014more than twice the tolerance of any commercial drives on the market\u2014and these characteristics were maintained for more than 60 hours, indicating exceptional stability and reliability.<\/p>\n
The team\u2019s findings, published in the journal Nature Electronics<\/em>, not only pave the way for better sensors for tools that need to operate in extreme environments but also open the door for AI systems adept at data-heavy computing in harsh conditions.<\/p>\n \u201cFrom deep-earth drilling to space exploration, our high-temperature memory devices could lead to advanced computing where other electronics and memory devices would falter,\u201d says Deep Jariwala, leader at the School of Engineering and Applied Science. \u201cThis isn\u2019t just about improving devices; it\u2019s about enabling new frontiers in science and technology.\u201d<\/p>\n The team developed a device that\u2019s classified as non-volatile, meaning it retains the information stored on it without needing an active power supply the like of which is used daily in consumer electronics in any device with a hard drive or flash drives. However, unlike other traditional silicon-based flash drive devices that start to fail at around 200\u00b0 Celsius (392\u00b0 Fahrenheit), the researchers designed theirs using a material known as ferroelectric aluminum scandium nitride (AlScN).<\/p>\n The researchers explain that AlScN confers a storage benefit by virtue of its ability to retain a given state of electrical state\u2014the \u201con\u201d or \u201coff\u201d representing 1s and 0s of digital data\u2014after an external electric field is removed and at significantly higher temperatures, among other desirable properties.<\/p>\n \u201cAlScN\u2019s crystal structure also gives it notably more stable and strong bonds between atoms, meaning it\u2019s not just heat-resistant but also pretty durable,\u201d says Dhiren Pradhan, the paper\u2019s first author and a postdoctoral researcher in the Jariwala and Olsson labs.<\/p>\n \u201cBut more notably, our memory device design and properties allow for fast switching between electrical states, which is crucial for writing and reading data at high speed.\u201d<\/p>\n The memory device consists of a metal\u2013insulator\u2013metal structure, incorporating nickel and platinum electrodes with a thin (45 nanometers) layer of AlScN, and thickness is a key consideration here, Jariwala says, because at elevated temperatures particles move more erratically.<\/p>\n \u201cIf it\u2019s too thin, the increased activity can drive diffusion and degrade a material. If too thick, there goes the ferroelectric switching we were looking for, since the switching voltage scales with thickness and there is a limitation to that in practical operating environments. So, my lab and Roy Olsson\u2019s lab worked together for months to find this Goldilocks thickness,\u201d he says.<\/p>\n This structural configuration also ensures compatibility with high-temperature silicon carbide logic devices, allowing the team\u2019s memory device to function in conjunction with high-performance computing systems designed for extreme temperatures.<\/p>\n Beyond building a robust storage device for terrestrial and extraterrestrial exploration, Jariwala and team also see this new technology\u2019s potential to enable more sophisticated forms of computation in extreme environments.<\/p>\n Jariwala explains that their device could also address a critical gap in current computing architectures where the separation of the central processing unit and memory creates inefficiencies, in that data must travel between these components, causing bottlenecks especially critical in artificial intelligence applications that process vast amounts of data rapidly.<\/p>\n \u201cConventional devices using small silicon transistors have a tough time working in high-temperature environments, a limitation that restricts silicon processors, so, instead, silicon carbide is used,\u201d he says.<\/p>\n \u201cWhile silicon carbide technology is great, it is nowhere close to the processing power of silicon processors, so advanced processing and data-heavy computing such as AI can\u2019t really be done in high-temperature or any harsh environments.<\/p>\n \u201cThe stability of our memory device could allow integration of memory and processing more closely together, enhancing speed, complexity, and efficiency of computing. We call this \u2018memory-enhanced compute\u2019 and are working with other teams to set the stage for AI in new environments.\u201d<\/p>\n <\/p>\n