Old Phase Change Material May Become New Phase Change Memory
Phase change memory is an upcoming technology that may become the standard medium for solid state data storage. Researchers are still looking for what would be the best material to use, and they have to carefully balance cost with effectiveness. Now researchers at Johns Hopkins University have found that a phase change material we have been using for about twenty years could be considerably faster and last longer than modern Flash memory.
Germanium, antimony, and tellurium comprise an alloy called GST (antimony’s atomic symbol is Sb). This material is cheap to make and is actually used in rewritable optical media, such as CD-RW and DVD-RW disks. It is used in these media because when it changes phase its optical properties and electrical properties change too.
Despite its common use, researchers have not understood the mechanics of how the material changes phase. This is because the change takes place in just nanoseconds. The Johns Hopkins researchers were able to slow down the process and with what they learned, they believe GST could be used for phase change memory that will operate 100 times faster than Flash and sustain 100,000 rewrites.