Protons key to next-generation memory chips

International team led byKing Abdullah University of Science and Technology (KAUST) found that the use of protons can provide multiple ferroelectric phase transitions. In simple terms, this means opening up new possibilities for creating memory chips with low power consumption and high capacity.

Ferroelectrics (such as indium selenide)are intrinsically polarized materials that reverse polarity when placed in an electric field, making them attractive for memory chips. In addition to low operating voltage, these devices exhibit excellent endurance during multiple read/write operations and high write speeds. However, their capacity is small, since existing technologies allow only a few ferroelectric phases to be launched, the capture of which is an experimentally difficult task.

To solve this problem, scientists appliedlayered indium selenide film on a structure consisting of an insulating sheet of alumina sandwiched between a layer of platinum at the bottom and porous silicon dioxide at the top. The platinum layer served as an electrode for the applied voltage, and the porous material acted as an electrolyte and “supplyed” protons to the ferroelectric film.

Researchers gradually introduced or removedprotons from the ferroelectric film by changing the applied voltage. In this case, several ferroelectric phases with different degrees of protonation were reversibly formed, which is of decisive importance for the implementation of multilevel memory devices with a significant memory capacity. The result of the experiment was to obtain a device operating at a voltage below 0.4 V - this is an important factor for the development of low-power high-speed memory cells. According to the researchers, the discovery will bring the era of the emergence of ferroelectric neuromorphic computing chips - fast and consuming less power than current solutions.