Researchers from the Institute of Physics of the Chinese Academy of Sciences have developed a new non-volatile memory that is up to 5,000 times faster than traditional storage devices. With the ability to read and write data within just a few nanoseconds, this “2D cousin” of flash memory can store multiple data bits instead of just 0s and 1s. In comparison, NAND flash and magnetic storage can only store information in the form of zeroes and ones.
This puts it on par with DRAM and other high-level volatile memory chips in terms of speed and performance. The chips consist of atomically thin layers of two-dimensional materials. When two or more layers of atoms of different elements are stacked upon one another to form a heterostructure, the resulting compound has hybrid properties. These layers are held by weak Van der Waal’s forces (yes the same one found in between graphite layers).
The researchers created a semiconducting layer of indium selenide, an insulating layer of hexagonal boron nitride, along with several conductive layers of graphites on top, held together by Van der Waals forces in a heterogeneous structure. These were placed upon silicon dioxide and silicon wafers. Turns out a voltage pulse lasting just 21 ns can charge the graphene electrons to write and erase data. The voltage is approximately the same as that used to write and erase data in flash memory.
Other than being blazing fast, this memory can also hold multiple bytes per cell. In traditional media, there can only be two states per cell, high or low, zero or one, on or off, etc. However, this particular alternative can store multiple data bits thanks to multiple electrical states, with each using a different voltage pulse sequence for writing and erasing.
As per estimates, this new kind of memory can hold data for up to 10 years, the same as existing forms of mature storage. The primary challenge is the mass production and integration of this memory into contemporary silicon semiconductors that have dominated the industry for decades now.