Bit Tech writes researchers from the University of California at Berkeley and Nanyang Technological University in Singapore have developed a new type of ferroelectric RAM (FeRAM) that does not destroy its contents when reading it. The discovery paves the way towards the commercialization of FeRAM, although there are still many challenges before this technology can take on DRAM and NAND flash memory:
Ramamoorthy Ramesh and Junling Wang, researchers from the University of California at Berkeley and Nanyang Technological University in Singapore claim to have solved the issue by creating a cheap and fast non-destructive read system based on visible light. Using a prototype FeRAM circuit based on bismuth ferrite, exploiting a property of the material discovered in 2009 by Rutgers University researchers whereby it creates a voltage as a result of light exposure, the team was able to read differing voltages depending on the polarity of the bit - reading back the stored data without destroying it.
While non-destructive read systems for FRAM have been developed in the past, they typically use expensive components - the first non-destructive FRAM read system, developed at NASA's Jet Propulsion Laboratory in 1991, used pulses from a powerful ultra-violet laser which the team admitted at the time 'would require a reduction in the [output] power by about an order of magnitude' before it could be used commercially.
The team's prototype shows real promise: according to figures released by the team as part of the paper's publication in the Nature journal, the bismuth ferrite FERAM circuit is capable of performing read and write operations in around 10 nanoseconds with a write voltage draw of 3V. By contrast, NAND flash components typically take thousands of times longer and require up to 15 volts.