A team of semiconductor companies made up of IBM, Matronix, and Qimonda have developed a material that made phase-change memory 500 to 1,000 times faster that traditional flash memory and requires half the power to record data. The memory is built on a 20nm process. Despite offering significantly faster performance, PRAM is similar to flash memory in that it's non-volatile and can retain data even if the host device is switched off. Unlike flash, though, PRAM can be written to an unlimited number of times. IBM and its partners may not introduce 20nm PRAM straight away, but Samsung has stated that it will start shipping PRAM in 2008.

Phase-change memory doesn't have that problem, suggesting it could be used far more widely than flash chips are today. "In the future, we want to target the disk drive, too," said Spike Narayan, senior manager for nanoscale science and technology at IBM. The chip industry is racing to find a replacement for flash memory, because the technology is expected to leak electrical current unacceptably when manufacturers shrink chip circuitry beyond certain dimensions. Phase-change memory is one of several candidates being considered. Memory chips have structures called cells, where data are recorded by the presence or absence of an electrical charge. By contrast, phase-change memory works by changing cells from an ordered, crystalline phase to a disordered, "amorphous" phase. In compact discs, similar phase changes are triggered by heat from a laser. Phase chips perform a similar feat using heat from electricity.