The battle over the next storage technology is heating up. IBM scientists this week demonstrated a working practical version of their Multi-bit Phase Change Memory. PCM combines speed, endurance, non-volatility and density into a single chip. This is Flash memory part 2 and may be the first technology to threaten hard drives. 100 times faster than flash with read/write durability of 10 million cycles this is what Flash always wanted to be. PCM is the little prince who one day may become the king of storage.
IBM developed a 200,000 memory cell test chip to prove the technology. The chip was developed using older 90nm CMOS fabricating technology – Intel is just about to start using 22nm technology – , the cells consists of an alloy between two electrodes, top and bottom. When voltage is passed between the electrodes the alloy heats up and changes once it hits the right temperature. This change in structure affects its electrical resistance and this is used to represent 1’s and 0’s. The alloy itself belongs to a class of materials called chalcogenide compounds, materials that change their internal structure from crystalline to amphoras under certain circumstances. DVD-R disks use a similar material but they use light to read and write, changing the refractive index.