The Flash Memory Summit has just begun, and to kick things off, Intel and Micron have announced something unexpected:  3 bit per cell flash memory.  This is significant on many levels (pun intended).  SLC (single level cell) flash is 1 bpc.  The vast majority of MLC (multi level cell) flash is 2 bpc, netting a 100% capacity gain over SLC.  This new flash is 3 bpc, pushing bit density to 200% over SLC and 50% over previous generation MLC flash.

Type
bits per cell
Cell voltage states
Relative cost
SLC
1
2
High
MLC 2
4
Average
MLC
3
8
Below Avergage

There is always a catch, but in this case it is not too bad.  Additional ECC overhead will be required to correct for bit errors that may occur as cell voltages drift slightly over time.  There would also be an increase in ‘program time’, since voltage accuracy would be a larger concern for data integrity, so the program circuitry would need to take a bit more time to zero in on just the right voltage.  This time increase is not such a big deal, since you are taking more time, but also writing more data.  3 bpc flash requires twice the voltage states per cell, meaning half the distance between state levels as compared to 2 bpc flash.  Here is a frame from a random product brief to help me illustrate the differences between bits per cell.

3 Bits are Better Than 2 - Storage  1

Above is the difference between 1 and 2 bpc.  3 bpc flash would be yet another doubling of the states,
and would effectively add another bit of data to the cell.

So what does this all mean to you?  In the long run, another 50% gain in capacity for your flash devices, namely SSDs.  We will be watching these developments closely as this new flash becomes available.
INTEL, MICRON ACHIEVE INDUSTRY’S MOST EFFICIENT NAND PRODUCT USING 3-BIT-PER-CELL TECHNOLOGY

Companies Hit Manufacturing Milestone Taking Advantage of 34-Nanometer NAND Process, To Deliver 32-Gigabit Density

SANTA CLARA, Calif. and BOISE, Idaho, Aug. 11, 2009 – Intel Corporation and Micron Technology Inc. today announced the development of a new 3-bit-per-cell (3bpc) multi-level cell (MLC) NAND technology, leveraging their award-winning 34-nanometer (nm) NAND process. The chips are typically used in consumer storage devices such as flash cards and USB drives, where high density and cost-efficiency are paramount.

Designed and manufactured by IM Flash Technologies (IMFT), their NAND flash joint venture, the new 3bpc NAND technology produces the industry’s smallest and most cost-effective 32-gigabit (Gb) chip that is currently available on the market. The 32Gb 3bpc NAND chip is 126mm². Micron is currently sampling and will be in mass production in the fourth quarter 2009. With the companies’ continuing to focus on the next process shrink, 3bpc NAND technology is an important piece of their product strategy and is an effective approach in serving key market segments.

“We see 3bpc NAND technology as an important piece of our roadmap,” said Brian Shirley, vice president of Micron’s memory group. “We also continue to move forward on further shrinks in NAND that will provide our customers with a world-leading portfolio of products for many years to come. Today’s announcement further highlights that Micron and Intel have made great strides in 34-nanometer NAND, and we look forward to introducing our 2xnm technology later this year.”

“The move to 3bpc is yet another proof point to the remarkable progress Intel and Micron have made in 34-nm NAND development,” said Randy Wilhelm, Intel vice president and general manager, Intel NAND Solutions Group. “This milestone sets the stage for continued silicon leadership on 2xnm process that will help decrease costs and increase the capabilities of our NAND solutions for our customers.”

Relevant Links
There are other ways to stay up-to-date on Micron and Intel news:
•    Micron Innovations Blog: http://www.micronblogs.com  
•    Micron on Twitter: http://twitter.com/microntechpr
•    Intel Pressroom: http://www.intel.com/pressroom
•    Intel Blog: http://www.blogs.intel.com
•    Intel on Twitter: http://twitter.com/intelnews

About Intel
Intel (NASDAQ: INTC), the world leader in silicon innovation, develops technologies, products and initiatives to continually advance how people work and live. Additional information about Intel is available at www.intel.com/pressroom and http://blogs.intel.com. For more details on Intel NAND flash solutions go to www.intel.com/go/ssd.

About Micron
Micron Technology, Inc., is one of the world’s leading providers of advanced semiconductor solutions. Through its worldwide operations, Micron manufactures and markets DRAMs, NAND flash memory, other semiconductor components, and memory modules for use in leading-edge computing, consumer, networking, and mobile products. Micron’s common stock is traded on the New York Stock Exchange (NYSE) under the MU symbol. To learn more about Micron Technology, Inc., visit www.micron.com.