Scientists at University of Pennsylvania have designed a phase-change memory in nanoscale that can fetch data 1,000 times faster than the flash memories we have today. The memory designed by assistant professor Department of Materials Science and Engineering, Ritesh Agarwal, consists of nanowires that can actually store the data for as long as 100,000 years and retrieve stored data up to 1,000 faster than conventional memory used today. The self-assembling nanowires are made from a germanium antimony telluride, which switches between amorphous and crystalline structures. The switching is the key to modern memory with read/write capabilities.
The memory was not made using lithography like today’s circuits, but through a method called self-assembly. With the assistance of nanoscale metal catalysts, the reactants are allowed to crystallize at lower temperatures and spontaneously form nanowires up to 10 µm in length and 50 nm in diameter. Then they fabricated the memory on silicon substrate.
After measuring the current amplitude needed for write access, switching speed between crystalline and amorphous structures, data retention time and long-term durability, they concluded that the memory had an exceptionally low power consumption of 0.7 mW per bit. The time needed for reading, writing or erasing data is as low as 50 ns, up to 1,000 faster than current flash memory.
The longevity of the nanowires was also estimated to be up to 100,000 years and the density of the memory to be in the terabit range.
“Imagine being able to store hundreds of high-resolution movies in a small drive, downloading them and playing them without wasting time on data buffering, or imagine booting your laptop computer in a few seconds as you wouldn’t need to transfer the operating system to active memory” Agarwal said.
