IBM scientists have demonstrated for the first time a relatively new memory technology, known as phase-change memory (PCM) that can reliably store multiple data bits per cell over extended periods of time. This significant improvement advances the development of low-cost, faster and more durable memory applications for consumer devices, including mobile phones and cloud storage, as well as high-performance applications, such as enterprise data storage.

PCM can write and retrieve data 100 times faster than Flash, enabling high storage capacities and no lose data when the power is turned off. Unlike Flash, PCM is also very durable and can endure at least 10 million write cycles, compared to current enterprise-class Flash at 30,000 cycles or consumer-class Flash at 3,000 cycles.

To achieve this breakthrough demonstration IBM scientists in Zurich used advanced modulation coding techniques to mitigate the problem of short-term drift in multi-bit PCM, which causes the stored resistance levels to shift over time, which in turn creates read errors. Up to now, reliable retention of data has only been shown for single bit-per-cell PCM, whereas no such results on multi-bit PCM have been reported.

IBM scientists say that memory chips based on PCM technology should come to the market within five years. PCM chips will offer a combination of speed, endurance, non-volatility and density unmatched by Flash.