Tuesday, 12 September 2006

Samsung Unveils Next Generation of Nonvolatile Memory - PRAM

Samsung has announced that it has completed the first working prototype of what is expected to be the main memory device to replace high density NOR flash within the next decade, a Phase-change Random Access Memory (PRAM)...

Samsung lifts the veil on PRAM. PRAM is an acronym for Phase-change Random Access Memory and the first prototype features 512Mbit capacity. It will combine the strength of standard RAM's processing speed with the non-volatile features of flash memory. Since PRAM is able to rewrite data without erasing previously accumulated data, it is theoretically 30 times faster than current flash memory. Commercial availability of the PRAM is slated for a 2008 release.

"Former chips were slower in saving and processing data," Kim Ki-nam, director at Samsung's semiconductor research centre, told Korean newspaper JoonAng Daily. "The PRAM is also much more cost-competitive, since the production process is actually simpler than for existing memory chips."

The company states that, PRAM will be a competitive choice over NOR flash, available beginning sometime in 2008. Samsung designed the cell size of its PRAM to be only half the size of NOR flash. Moreover, it requires 20 percent fewer process steps to produce than those used in the manufacturing of NOR flash memory.

Adopting the use of vertical diodes with the three–dimensional transistor structure that it now uses to produce DRAM developed Samsung’s new PRAM. The new PRAM has 0.0467um 2 cell size of any working memory that is free of inter-cell noise, allowing virtually unlimited scalability.

PRAM works by electrically heating tiny amounts of chalcogenide, a material currently used in rewritable DVDs. The material can cool into one of two states with different electrical conductivity, thus storing binary data that persists when power is removed. This gives the technology the potential to be used across the entire IT industry, providing it has the as-yet undemonstrated ability to scale into smaller and faster devices over time, supporting future generations of devices.

Problems PRAM faces include long-term storage stability, the number of read/write cycles it can withstand and sensitivity to high temperatures. Samsung claims its chip can preserve data for more than two years, even in high temperatures of 85C, and is a thousand times more durable than existing flash memory chips.