A technology revealed by IBM may replace flash and lead to 100 times faster storage

Among other things, the memory chip will allow it to be used as a memory system for cell phones and mobile devices that will be cheap and reliable

IBM has revealed significant progress on the way to developing a new technology for computer memories, known as phase-change memory (PCM), which will enable a leap forward in the world of information technology and storage.

The PCM technology developed by researchers at the IBM research laboratory in Zurich is currently considered the most promising alternative to existing memory and storage technologies such as flash memory and may enable new levels of performance in the years to come. It foreshadows the potential for stable and dense storage of data, at a speed 100 times higher and with levels of reliability and durability better than those of flash memories that are known and common today, from USB interface storage devices to SSD disks. Thus, for example, PCM technology will make it possible to boot computers and servers immediately, while significantly improving the performance of information technology systems. Unlike flash memories that exist today, which are limited to the activity of about 30,000 write and erase cycles - PCM components can perform 10 million cycles of such operations before a decrease in their performance is recorded.

The significant improvements that IBM scientists made to the technology shorten the way to developing cheaper, faster and more durable memory systems for consumer devices - including cell phones - as well as for a cloud storage environment, and for high-performance systems such as corporate storage servers.

As organizations and customers increasingly adopt cloud computing models, in which most of the information is stored and processed in the cloud environment, storage means with higher power and a more affordable price are required, both at the level of internal memory and at the level of memory currently managed in disks or flash memory chips and disks based on them (SSD) .

IBM predicts, as mentioned, that the new technology will enable a leap forward in the world of information technology and corporate storage, including a cloud computing environment - which is expected to be realized by 2016.
The IBM researchers were able, for the first time, to prove that a PCM memory cell can reliably store several bits of information in each cell, for a long time. In order to show this reliability, the developers at IBM were required to improve key points in the writing and reading processes of the memory. They used advanced coding techniques, which make it possible to minimize the extent of the problem of changing the bits of information created over time.

To date, researchers have been able to reliably store only a single bit of information in each PCM memory cell. Storage of more than one massive, caused problems of change in the level of electrical resistance created over time and generates disruptions in reading the data.

PCM technology is based on monitoring the change in the electrical resistance level of the material - an alloy of several components. The change from a crystal state, characterized by low resistance, to an amorphous state, which exhibits high resistance - represents a change in a single chip. A PCM memory cell consists of the phase change material, which is placed between a top electrode and a bottom electrode. The control of the phase change is carried out by passing a current of different intensities between these two electrodes. The transfer of the current heats the material that changes the phase, and crossing defined threshold values ​​of temperature leads to the phase change which gives rise to a change in the electrical resistance - which can be used for recording a single bit of information (0 or 1 indication in a state of high or low resistance).

The intensity of the current transmitted through the material determines how much of the material placed between the electrodes will undergo a phase change - which in turn will directly affect the resistance of the entire cell. The scientists estimate that in this way it will be possible to store more than one mass in each memory cell. In the current work, IBM scientists used four different levels of resistance to store the combinations 00, 01, 10 and 11.

The new sophisticated measurement method, developed by the researchers for the purpose of accurately reading the information stored in such a cell, is based on measuring the required deviation in the strength of the electrical signals. The maximum latency level in the new writing process is 10 microseconds - a hundred times faster than the most advanced non-volatile memories available today.
The chips that the researchers were able to produce as part of the current experiment include 200 memory cells, and are produced in a standard CMOS process in the industry, using 90 nanometer technology. The creation of the experimental chip was carried out in collaboration between IBM researchers and scientists in Zurich, engineers at the IBM factories in Burlington-Vermont and Yorktown, New York. The experimental chip operated successfully for more than five consecutive months, proving that multi-bit PCM chips for each storage cell are indeed able to reach reliability levels suitable for practical applications.