Jan 18 2018
Engineers all over the world have been developing alternative ways for providing greater memory storage capacity on even smaller computer chips. Earlier research on two-dimensional atomic sheets used for memory storage has failed to expose their potential - until now.
Illustration of a voltage-induced memory effect in monolayer nanomaterials, which layer to create "atomristors," - the thinnest memory storage device. It could lead to faster, smaller and smarter computer chips. (Image credit: Cockrell School of Engineering, The University of Texas at Austin)
A team of electrical engineers at The University of Texas at Austin, in association with Peking University scientists, has produced the thinnest memory storage device comprising of dense memory capacity, making room for smaller, faster and smarter computer chips for everything starting from consumer electronics to brain-inspired computing to big data.
"For a long time, the consensus was that it wasn't possible to make memory devices from materials that were only one atomic layer thick," said Deji Akinwande, Associate Professor in the Cockrell School of Engineering's Department of Electrical and Computer Engineering. "With our new 'atomristors,' we have shown it is indeed possible."
Developed from 2D nanomaterials, the "atomristors" - a term Akinwande coined - enhance upon memristors, a developing memory storage technology comprising of lower memory scalability. He and his team featured their findings in the January issue of Nano Letters.
Atomristors will allow for the advancement of Moore's Law at the system level by enabling the 3D integration of nanoscale memory with nanoscale transistors on the same chip for advanced computing systems.
Deji Akinwande
Transistors and memory storage have, to date, always been separate components on a microchip, but atomristors merge both functions on a more efficient, single computer system. By employing semiconducting atomic sheets (molybdenum sulfide) as the active layer and metallic atomic sheets (graphene) as electrodes, the whole memory cell is a sandwich about 1.5 nm thick, which allows it possible to densely pack atomristors layer by layer in a plane. This is a substantial benefit over standard flash memory, which occupies far greater space. Furthermore, the thinness permits for more efficient and faster electric current flow.
Given their capacity, size and integration flexibility, it is possible to pack together atomristors in order to make improved 3D chips that are vital for the successful development of brain-inspired computing. One of the paramount challenges in this growing field of engineering is how to produce a memory architecture with 3D connections similar to those discovered in the human brain.
The sheer density of memory storage that can be made possible by layering these synthetic atomic sheets onto each other, coupled with integrated transistor design, means we can potentially make computers that learn and remember the same way our brains do.
Deji Akinwande
Another exceptional application for the technology was also discovered by the team. In current ubiquitous devices such as tablets and smartphones, radio frequency switches are employed for connecting incoming signals from the antenna to one of the several wireless communication bands, enabling different parts of a device to communicate and then cooperate with one another. This activity can considerably impact a smartphone's battery life.
The atomristors are the tiniest radio frequency memory switches to be established with no DC battery consumption, which can eventually result in longer battery life.
"Overall, we feel that this discovery has real commercialization value as it won't disrupt existing technologies," Akinwande said. "Rather, it has been designed to complement and integrate with the silicon chips already in use in modern tech devices."