New Design for Computer Memory Could Reduce Energy Demands

Wednesday - July 5 2023, 04:52 UTC - 1 year ago

Researchers have developed a new design for computer memory which could greatly improve performance, reduce the energy demands of internet and communications technologies, and lead to the development of computer memory devices with far greater density, higher performance and lower energy consumption.

Researchers have developed a new design for computer memory that could both greatly improve performance and reduce the energy demands of internet and communications technologies, which are predicted to consume nearly a third of global electricity within the next ten years.The researchers, led by the University of Cambridge, developed a device that processes data in a similar way as the synapses in the human brain. The devices are based on hafnium oxide, a material already used in the semiconductor industry, and tiny self-assembled barriers, which can be raised or lowered to allow electrons to pass. This method of changing the electrical resistance in computer memory devices, and allowing information processing and memory to exist in the same place, could lead to the development of computer memory devices with far greater density, higher performance and lower energy consumption. The results are reported in the journal Science Advances.

Our data-hungry world has led to a ballooning of energy demands, making it ever-more difficult to reduce carbon emissions. Within the next few years, artificial intelligence, internet usage, algorithms and other data-driven technologies are expected to consume more than 30% of global electricity.

"To a large extent, this explosion in energy demands is due to shortcomings of current computer memory technologies," said first author Dr. Markus Hellenbrand, from Cambridge's Department of Materials Science and Metallurgy. "In conventional computing, there's memory on one side and processing on the other, and data is shuffled back between the two, which takes both energy and time." .

One potential solution to the problem of inefficient computer memory is a new type of technology known as resistive switching memory. Conventional memory devices are capable of two states: one or zero. A functioning resistive switching memory device however, would be capable of a continuous range of states—computer memory devices based on this principle would be capable of far greater density and speed.

"A typical USB stick based on continuous range would be able to hold between 10 and 100 times more information, for example," said Hellenbrand.

Hellenbrand and his colleagues developed a prototype device based on hafnium oxide, an insulating material that is already used in the semiconductor industry. The issue with using this material for resistive switching memory applications is known as the uniformity problem. At the atomic level, hafnium oxide has no structure, with the hafnium and oxygen atoms randomly mixed, making it challenging to use for memory applications.

However, the researchers found that by adding barium to thin films of hafnium oxide, some unusual structures started to form, perpendicular to the hafnium oxide plane, in the composite material.

These vertical barium-rich 'bridges' are highly structured, and allow electrons to pass through, while the surrounding hafnium oxide remains unstructured. At the point where these bridges meet the device contacts, an energy barrier was created, which electrons can cross. The researchers were able to control the height of this barrier, which in tu raised and lowered the resistance of the material.