EETimes recently posted a column written by Ed. Doller, Chief Technology Officer of Intel's flash memory spin-off Numonyx, in which he addresses the growing concerns for alternative solutions to NAND-flash memory insufficiencies.
The column highlights several aspects of Solid State Disk endurance requirements meeting application demands, particularly in the enterprise market where storage reliability and scalability are mission-critical aspects of data maintenance. What caught our attention, however, was Mr. Doller's seasoned opinions on phase-change memory serving as a viable long-term replacement solution for the growing concerns of NAND-flash endurance.
"Remember with any non-volatile floating gate memory device, the more you cycle the device the more failures you tend to observe, and the less data retention you get," stated Dollar. "One alternative to [NAND-flash] that holds tremendous promise is phase-change memory (PCM). Much has been said and written about PCM, but what is interesting about PCM is that retention is decoupled from endurance."
In perspective, one of the main advantages that phase-change memory has over NAND-flash is its ability to cycle data millions and millions of times and hold a very steady level of data retention. In contrast, the NAND-flash memory used in conventional SSDs impose quite different usage conditions as they are limited by read-write cycles causing increased performance degradation and lower MTBF occurrences over time.
Nevertheless, Mr. Dollar predicts that 2010 could be the year that this industry sees conventional NAND-flash SSD technology "topping out." However, the good news is that there is hope for a very promising phase-change memory alternative that should be taken into consideration as R&D engineers plan for more viable and stable storage approaches as the decade progresses.