Search the site...

  phil mora
  • The Global Nomad
  • About
  • Contact
  • The Training Log
  • The Global Nomad
  • About
  • Contact
  • The Training Log

The Global Nomad
(Doer edition)

Follow

Denser, Faster Memory Challenges Both DRAM and Flash

8/14/2013

0 Comments

 
Picture
Picture
Picture
Picture
A new memory technology can store a terabyte on a chip the size of a postage stamp.

Why it matters: Existing memory technologies cannot offer much more improvements in data storage density.

[Thank you MIT Technology review]
[ By Tom Simonite | 08.14.13]


More memory: The memory storage device shown in this electron micrograph image could enable dramatic jumps in the capacity of memory cards and other digital data stores.

A new type of memory chip that a startup company has just begun to test could give future smartphones and other computing devices both a speed and storage boost. The technology, known as crossbar memory, can store data about 40 times as densely as the most compact memory available today. It is also faster and more energy efficient.

The technology’s ability to store a lot of data in a small space could see it replace the flash memory chips that are the basis of memory cards, some hard drives, and the internal storage of mobile devices. Data can be accessed and written to crossbar memory fast enough to see it also possibly compete with DRAM, used as short-term memory, in computing devices. The technology is significantly more energy efficient than both flash and DRAM.
“It will be much denser and faster than flash because it is not based on moving electrons around or on transistors,” says Wei Lu, a professor at the University of Michigan whose research led to the development of crossbar memory. Lu is also a cofounder and chief scientist of the Santa Clara, California-based startup Crossbar, which is commercializing the technology. He notes that initially the company is developing its technology to replace flash storage.

Demonstration crossbar memory chips are being made by TSMC, the world’s largest contract chip manufacturer. Crossbar says that the current version of the technology can store one terabyte of data (1,000 gigabytes) on a single chip 200 square millimeters, about the size of a postage stamp. By comparison, the densest flash memory chips on the market today store 16 gigabytes on a single chip. The smallest such chip, introduced by Micron in May this year, is 144 square millimeters in area.

Crossbar memory is so called because of the simple nanoscale structure used to store data. Two layers of evenly spaced, rod-like electrodes are stacked on top of one another, with the rods of the top layer oriented at 90 degrees to those of the layer below to form a grid. Bits of data—1s and 0s—are stored at each of the junctions where electrodes from the different layers cross.

That basic crossbar architecture has been used for years as the basis of new ideas in electronics, including for memory (see “Molecular Memory”). However, Lu’s version is different in how it stores data at the junctions, using a simple spacer made from amorphous silicon at each junction rather than a more exotic material.

In Crossbar’s chips, that spacer separates the electrode from the upper layer, made from silver, from that of the lower layer, made from a nonmetallic conductor. Bits are stored by having that spacer flip between being an insulator and a conductor—sometimes allowing current to pass between the upper and lower electrodes, sometimes blocking the current. The spacer can retain its state, and hence a bit, without power.

Data is written by applying a specific control voltage to a particular crossbar junction. Applying a positive voltage causes silver nanoparticles to creep out from the upper rod into the silicon spacer, eventually penetrating far enough to create an electrical path between the upper and lower rods so that current can flow. Applying a negative control voltage can reverse that process. Data is read out from crossbar memory by testing the conductivity of each junction.

In the demonstration chips being produced today, one layer of crossbar memory structures is stacked on top of a layer of conventional silicon CMOS circuitry. That circuitry reads, writes, and erases data from the crossbar memory layers overhead.

Crossbar, which has received $25 million in investment funding from Kleiner Perkins Caufield & Byers, Artiman Ventures, and Northern Light Venture Capital, began working to commercialize Lu’s research in 2010. A crucial part of the development process was adapting the novel technology for mass manufacturing in existing chip factories, says Lu. Experimentation was required to determine how to deposit the novel crossbar structures on top of conventional CMOS circuitry. “You don’t want to contaminate the CMOS layer or to raise the temperature so much that it gets damaged,” says Lu.

Crossbar’s technology is preparing for market at a time when memory manufacturers are struggling to squeeze more data density out of existing methods of making flash memory, says Brian Cronquist, a vice president of Monolithic 3D, a company developing 3-D chip architecture designs. “The ways they used to scale flash memory don’t work anymore.”

Flash memory chips store data as islands of charge on a surface, but those islands cannot be packed any tighter than they are today, making improvements in density practically impossible. That has driven Samsung and Toshiba to work on 3-D flash memory chips, which stack up multiple charge-storing surfaces. Samsung produced working chips ready for mass production earlier this year.

However, Cronquist says, that approach won’t deliver gains for more than a few years, so a new technology will need to take over. Crossbar’s is one possible contender, he says, among others in development.

One of those is HP’s, based on an electrical component known as the memristor, which was predicted to exist in 1971 but first made only in 2008 (see “Memristor Memory Readied for Production”). HP said as recently as last year that it would launch the technology in late 2013, but it has not recently confirmed its plans.

Read more: http://www.technologyreview.com/news/517996/denser-faster-memory-challenges-both-dram-and-flash/
0 Comments



Leave a Reply.

    i blog about the things I love: fitness, hacking work, tech, Experiences and anything holistic.

    Picture

    Phil Mora

    > Head of Digital  Product at Nutrien
    > I am passionate about delivering products and technologies that change people's lives
    ​> I look forward to connecting with you!

    Categories

    All
    Change Agents
    Experiences
    Fitness
    Hacking Work
    Technology

    Archives

    January 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    July 2020
    June 2020
    May 2020
    April 2020
    March 2020
    February 2020
    January 2020
    December 2019
    November 2019
    October 2019
    July 2019
    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    July 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    January 2016
    October 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    January 2014
    December 2013
    November 2013
    October 2013
    September 2013
    August 2013
    July 2013
    June 2013
    May 2013
    April 2013
    February 2013
    January 2013
    December 2012
    August 2012
    July 2012
    June 2012
    May 2012
    April 2012
    March 2012
    January 2012
    December 2011
    October 2011
    September 2011
    August 2011
    June 2011
    May 2011
    April 2011
    March 2011
    February 2011
    January 2011
    December 2010
    November 2010
    October 2010
    September 2010
    August 2010
    July 2010

    RSS Feed

Phil Mora . 2225 E Bayshore Road . Palo Alto, CA 94393
Phone: (415) 315-9787 . twitter
@philippemora . Instagram philippemora


Copyright © 1999-2020 Philippe Mora