The Japanese company Floadia has developed a flash memory that allows you to write 7 bits of data into one cell, as well as store them for 10 years at temperatures up to 150 ° C. For comparison, modern flash-based drives assume writing no more than 4 bits per cell.
The development was based on the SONOS technology (Silicon-Oxide-Nitride-Oxide-Silicon), created for microcontrollers, in which some changes were made. The company has changed the structure of the charge-retaining layers by using Ono film, in addition, the structure of the cell and the storage controller have changed. As the developers clarified, without making all these changes, 7 bits in the cell were held for no more than 100 seconds.
The existing 3D QLC NAND flash memory technology on the market assumes recording 4 bits per cell and a “margin of safety” for about 1000 rewriting cycles at normal temperature. In the initial version, Floadia SONOS technology offers a higher number of rewriting cycles (up to 100,000 times) and the ability to store data for a longer time (up to 10 years). But there is a nuance. It is intended for microcontrollers that do not require large amounts of data and are manufactured on the basis of outdated technological processors (55-350 nm). As a result, the memory density of the drive is inferior to traditional modern technologies, the speed of the modules is also low.
Nevertheless, the new Floadia technology will be able to be used in solutions involving in-memory computing — the company intends to use the invention in accelerators for artificial intelligence systems, in which it will provide higher performance indicators in comparison with current solutions. Floadia traditionally licenses its technologies to interested manufacturers. It is unclear whether the company will be able to refine its technology for use in traditional 3D NAND memory chips.
Source: tomshardware.com