FeTRAM memory could be faster than SRAM and more energy efficient than flash
By Darren Quick
September 27, 2011
Researchers at Purdue University are developing a new type of computer memory that they claim could be faster than SRAM and use 99 percent less energy than flash memory. Called FeTRAM, for ferroelectric transistor random access memory, the new technology fulfills the three basic functions of computer memory; writing, reading and storing information for a long time. It is also a nonvolatile form of memory, meaning that it retains its data after the computer has been turned off. Its creators claim it has the potential to replace conventional memory systems.
The new FeTRAM memory is similar to ferroelectric random access memories, (FeRAMs), which are used in industrial and automotive applications. While both use ferroelectric material - one that switches polarity when electric fields are applied - to store information and both are nonvolatile, FeRAMs use a ferroelectric capacitor, which means the information is lost after it is read.
FeTRAMS, on the other hand, store information by reading the changing polarity of ferroelectric transistors as a 0 or 1, which allows for nondestructive readout. These ferroelectric transistors are created by combining silicon nanowires with a ferroelectric polymer. The researchers say the new technology is also compatible with current CMOS, (complementary metal oxide semiconductors), manufacturing methods.
"You want to hold memory as long as possible, 10 to 20 years, and you should be able to read and write as many times as possible," doctoral student Saptarshi Das, who is working with Joerg Appenzeller, a professor of electrical and computer engineering and scientific director of nanoelectronics at Purdue's Birck Nanotechnology Center. "It should also be low power to keep your laptop from getting too hot. And it needs to scale, meaning you can pack many devices into a very small area. The use of silicon nanowires along with this ferroelectric polymer has been motivated by these requirements."
Although the researchers claim the FeTRAM technology has the potential to use 99 percent less energy than flash memory, this hasn't yet been achieved.
"We've developed the theory and done the experiment and also showed how it works in a circuit," said Das. "However, our present device consumes more power because it is still not properly scaled. For future generations of FeTRAM technologies one of the main objectives will be to reduce the power dissipation. They might also be much faster than another form of computer memory called SRAM."