A few months ago, we brought news of a bendable CPU, termed Plastic ARM, that was built of amorphous silicon on a flexible substrate. The use cases for something like this are extremely low-powered devices that can be embedded in clothing or slapped on the surface of irregular objects, allowing them to have a small amount of autonomous computing. But to meet the low power requirements, a minimalist processor is not enough—all the components have to sip power as well. And that makes for a poor fit for traditional RAM technology, which needs power to maintain the state of the memory.
But a group from Stanford now has that covered. The researchers have built a form of flexible phase-change memory, which is closer in speed to normal RAM than flash memory but requires no power to maintain its state. And, while their work was initially focused on getting something that's flexible to work, the principles they uncovered during their work should apply to phase-change memory in general.
[...] A lot of flexible electronics are built on polymer substrates rather than rigid materials like silicon. In addition to being flexible, most polymers are insulators—they don't conduct electricity or heat very well. And that turned out to be critical to boosting the efficiency of the phase-change memory.
The gist of the new device is that the phase-change hardware is surrounded by materials that don't conduct heat well. This helps trap the heat required to partially melt the device where it's needed, which means that you don't have to generate as much heat in the first place. And that in turn means that you need to put less power in to reset the device.