Print 31 comment(s) - last by rushfan2006.. on Jan 30 at 10:19 AM

An ultra-dense 160-kilobit memory made up of a 400 x 400 grid of nanowires

Two-state rotaxane molecules act as switches

The memory chip placed among white blood cells for size comparison
Researchers create memory circuit the size of a human white blood cell

A team of UCLA and California Institute of Technology chemists has created an ultra-dense memory device that stores information using reconfigurable molecular switches. The 20 kilobyte memory device has a bit density of 100 gigabit per square centimeter and has enough capacity to store the Declaration of Independence with space left over. The accomplishment represents an important step toward the creation of molecular computers that are much smaller and could be more powerful than today's silicon-based computers.

“Using molecular components for memory or computation or to replace other electronic components holds tremendous promise,” said J. Fraser Stoddart, who is the Fred Kavli Chair in Nanosystems Science at UCLA and director of the California NanoSystems Institute. “This research is one of the only examples of building large molecular memory in a chip at an extremely high density, testing it, and working in an architecture that is practical, where it is obvious how information can be written and read.”

The memory is based on a series of perpendicular, crossing nanowires, similar to a tic-tac-toe board: 400 silicon wires crossed by 400 titanium wires, each 16 nanometers wide. Sitting at each crossing of the tic-tac-toe structure and serving as the storage element are approximately 300 bistable rotaxane molecules. These molecules may be switched between two different states, and each junction of a crossbar can be addressed individually by controlling the voltages applied to the appropriate top and bottom crossing wires, forming a bit at each nanowire crossing.

Hewlett-Packard researchers just last week announced a breakthrough in using nanowires in transistor assembly as well.

“For this commercial dream to be realized, many fundamental challenges of nano-fabrication must be solved first,” Stoddart said with regard to Caltech's breakthrough. “The use of bistable molecules as the unit of information storage promises scalability to this density and beyond. However, there remain many questions as to how these memory devices will work over a prolonged period of time. This research is an initial step toward answering some of those questions.”

“We have shown that if a wire is broken or misaligned, the unaffected bits still function effectively; thus, this architecture is a great example of 'defect tolerance,' which is a fundamental issue in both nanoscience and in solving problems of the semiconductor industry,” Stoddart explained. “This research is the culmination of a long-standing dream that these bistable rotaxane molecules could be used for information storage.”

“It's the sort of device that Intel would contemplate making in the year 2020,” says James Heath, who is the Gilloon Professor at Caltech. “But at the moment it furthers our goal of learning how to manufacture functional electronic circuitry at molecular dimensions.”

The 2020 date assumes the validity of Moore's Law, which states that the complexity of an integrated circuit will typically double every year, leading to a projection that the electronics industry will achieve a device density comparable to the memory circuit in about 13 years.

However, the Caltech-UCLA team points out in their report that manufacturers can see no clear way at present of extending this miniaturization beyond the year 2013. The new approach of the Heath team, therefore, will show the potential for making integrated circuits at smaller and smaller dimensions.

“Our goal was not to demonstrate a robust technology; the memory circuit we have reported on is hardly that,” said Heath. “Instead, our goal was to demonstrate that large-scale, working electronic circuits could be constructed at a density that is well-beyond 10-15 years where many of the most optimistic projections say is possible.”

“Molecular switches will lead to other new technologies beyond molecular electronic computers,” Stoddart said. “It is too soon to say precisely which ones will be the first to benefit, but they could include areas such as health care, alternative energy, and homeland security.”

Stoddart, his collaborator James R. Heath, the Elizabeth W. Gilloon Professor of Chemistry at the California Institute of Technology, and their research teams report the work in the January 25 issue of the journal Nature. The research was funded primarily by the National Science Foundation and the Defense Advanced Research Projects Agency.

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it can't be just me
By lufoxe on 1/29/2007 9:08:51 AM , Rating: 2
I see useful everyday use for this, but why is it the first thing that comes to mind is military applications. (silent killers anyone?)

RE: it can't be just me
By Etern205 on 1/29/07, Rating: -1
RE: it can't be just me
By GoatMonkey on 1/29/2007 9:30:41 AM , Rating: 3
Do you know how much of the stuff you use every day was created as an offshoot of wartime technology development?

I'll agree that the U.S. needs to spend more on research, but we're far from being left in the dust in many categories.

RE: it can't be just me
By masher2 on 1/29/2007 10:15:46 AM , Rating: 3
> "the US use most of it's money are war weapons that's why!"

This must be some strange usage of the word "most" that I'm unfamiliar the US only spends 3.5% of its GDP on the military.

It'd be even less, by the way, if it wasn't for certain European nations that don't want to pay to defend themselves.

RE: it can't be just me
By rushfan2006 on 1/29/07, Rating: -1
RE: it can't be just me
By masher2 on 1/29/2007 10:48:03 AM , Rating: 3
> "This was nearly five times more than the next highest departmental budget."

Total Federal spendings, 2006:

Social Security: 21%
Medicare & Medicaid: 21%
Military & Domestic Security: 19%
Nonmilitary Discretionary Spending: 18%
Interest on the Debt: 9%
Other: 12%

RE: it can't be just me
By Spivonious on 1/29/2007 11:04:52 AM , Rating: 2
So we're spending over $37 billion on interest? Crazy.

RE: it can't be just me
By kenji4life on 1/29/2007 11:05:27 AM , Rating: 2
While your statement may be true, I must point out that rushfan did say:
Also realize my source for the budget information doesn't itemize. So that 420 billion is for ALL DoD, equipment/weapons, administrative personnel, everything.

So there is conflicting information between the two of you. I haven't looked into what exactly, so I don't know what it is.

RE: it can't be just me
By kenji4life on 1/29/2007 11:08:54 AM , Rating: 2
perhaps this table would be of assistance.

RE: it can't be just me
By rushfan2006 on 1/29/2007 12:00:06 PM , Rating: 2
Well just so you know I didn't pull my information out of my is how I got there...

Go to :

Then I merely looked through each individual departement and looked what was spent. Get to the DoD and you see the 419b figure which far out paced the budgeting of any other department.

RE: it can't be just me
By masher2 on 1/29/2007 1:18:06 PM , Rating: 2
You're looking at discretionary budgets, not total budget. The total budget for a department is a sum of its discretionary + mandatory figures. Mandatory spending is that which is required by law, and not subject to congressional approval.

Defense is primarily discretionary spending, whereas Social Security and entitlement programs such as Medicare and Medicaid are almost entirely mandatory.

RE: it can't be just me
By FITCamaro on 1/29/2007 1:34:05 PM , Rating: 3
Don't forget the billions we shell out to Israel and other countries in the Middle East and our troops in Korea. I'm sure even then I'm missing something. And thats just military aid. Never mind the billions we give to other countries for food, medicines, post-disaster help, etc. Where was the rest of the world when we got hit by Katrina? I believe 2 nations offered some assistance?

If Europe is so high and mighty they're free to fund the UN. As of now the US primarily funds any UN operations since its our troops and people being sent nearly all the time. Personally I think the US needs to pull out of the UN and let the rest of the world handle its own problems since everyone seems to want to bitch about how we do it. Save our billions of dollars for our own people since Europe and other countries don't appreciate it when they don't even come close to giving as much as we do. We've got far better things to spend it on here at home.

RE: it can't be just me
By Live on 1/29/2007 8:40:31 PM , Rating: 3
I lot of nations "offered" support. But the US declined. The way international disaster aid is handled is that the country that is in need of assistance ask for what it needs. The US didn't ask for much if anything.

The reason behind this is because in the past country's got a lot of "help" they didn't need. Used clothes to combat starvation in Africa is one good example.

Why the US didn't ask for much help I don't know. But it wasn't because they couldn't get any, thats for sure.

RE: it can't be just me
By Felofasofa on 1/29/2007 9:44:00 PM , Rating: 2
Maybe you guys should have asked for help, because the relief effort was appalling, look what happened in that stadium. Then you had the ridiculous situation of Black Hawks going around picking up individuals! Absurd use of resources. The whole effort was a joke. Just tossing money at problems doesn't always solve things. I think with government spending people ought to focus on quality on quantity.

RE: it can't be just me
By Felofasofa on 1/29/2007 9:48:43 PM , Rating: 2
quality on quantity.

fuckit.... quality not quantity

RE: it can't be just me
By just4U on 1/30/2007 2:22:18 AM , Rating: 2
err .. you forgot to include Canadian forces in your post. I do believe we make up a large part of UN forces as well.

RE: it can't be just me
By just4U on 1/30/2007 2:24:21 AM , Rating: 2
and we did send aid for Katrina! But being American you most likely know that :)

RE: it can't be just me
By dustwalker13 on 1/30/2007 9:57:47 AM , Rating: 1
um ... sure ... what color has the sky in the world you life in by the way?

sorry but the only reason for the wars, the us fought in the last decade, was resources - mainly oil to be specific. the us even supportet saddam hussein and bin laden, because it was fafourable at that time.

stop telling us, you are the good guys, all here for the rescue of those poor little europeans ... this storry is starting to get really old. there wouldn't be anything to defend from if your nation hadn't startet messing things up for a few cents per barrel!

RE: it can't be just me
By rushfan2006 on 1/30/2007 10:19:36 AM , Rating: 2
stop telling us, you are the good guys, all here for the rescue of those poor little europeans ... this storry is starting to get really old. there wouldn't be anything to defend from if your nation hadn't startet messing things up for a few cents per barrel!

I agree this whole line of debate over who are the good guys and the reason for wars caused and fought over the years is all very tiring.


Read your history books, hell they have good documentaries you can rent from public libraries now -- every major nation from England to Ireland to Scotland....Canada...Mexico....of course the whole of the Middle East, Italy....the United States.....and on and on all have there "dirty little" secrets and all have their seemingly immoral or unethical motivations and causes for war at some point in time.

I think its funny (not in a "ha ha way") that people will toke up this notion of "its your country that is the bad guys" ...WHAT..."my country are the good guys go screw yourselfs".......ignorance and bullshit.

And btw...why is it a sin to kill for oil? Yes I said it. Going after an extremely important resource that fuels a nation seems logical to go to war over. Again...its not the first time wars were fought over resources....and please -- America is hardly the inventor of the concept of fighting a war over resources.

What I want to know is...
By wrekd on 1/29/07, Rating: 0
RE: What I want to know is...
By KeithTalent on 1/29/2007 10:59:32 AM , Rating: 4
Try religion, as I don't think science can help you there ;-)

RE: What I want to know is...
By masher2 on 1/29/2007 1:37:30 PM , Rating: 1
Too bad I can't vote, as your post certainly deserves a much higher score than the one to which you responded.

RE: What I want to know is...
By wrekd on 1/29/2007 5:39:42 PM , Rating: 4
And I certainly deserved that verbal "mashing" for an obvious attempt at cheap humor. Atleast KeithTalent added the ;-) to show that no offense was intended.

I wonder, what were your intentions and how should you be scored?

RE: What I want to know is...
By masher2 on 1/30/2007 9:16:42 AM , Rating: 2
I wasn't attempting to disparage you, but rather those voters who (at the time of my original post) had downrated his reply to zero. Its up to three now, so apparently a few people agreed with me. :)

When? =)
By Mudvillager on 1/29/2007 8:45:17 AM , Rating: 2
My mind must be clouded or something but I can't make out when they're predicting this can go mainstream...

RE: When? =)
By bkiserx7 on 1/29/2007 9:48:20 AM , Rating: 3
I think they were saying 2020 if they could manufacture on a mainstream basis and the memory seems to be stable on a long term basis. My question is, when the molecular switch "fails" does it completely fail or can it be switched back on/off?

RE: When? =)
By masher2 on 1/29/2007 1:59:41 PM , Rating: 2
> " think they were saying 2020 if they could manufacture on a mainstream basis ..."

Actually, they were saying almost the exact opposite; that they have no estimates for when the technology might be commercialized ("Our goal was not to demonstrate a robust technology..."). The 2020 figure was merely a Moore's Law projection on when such small components would be required.

Good density, but what about performance?
By Hoser McMoose on 1/29/2007 1:13:22 PM , Rating: 2
The density on this is fairly impressive. For comparison, Intel fairly recently demonstrated SRAM cells built on a 45nm production line that had a memory cell size of 0.346um^2, or about 289Mbit/cm^2. At 100Gbit/cm^2 this is almost 3 orders of magnitude higher density, which is very impressive.

However what is the performance of this thing? Size vs. speed (and cost) has always been a key trade-off in computers. Should we really even be bothering comparing this to SRAM? Is the performance more in-line with DRAM, or worse yet, hard disks? Hard disks are already at about 20Gbit/cm^2 with current hard disks and should easily hit 100Gbit/cm^2 before this technology hits mainstream. So if the performance is no better than a hard disk then it's really not very impressive.

RE: Good density, but what about performance?
By masher2 on 1/29/2007 1:40:19 PM , Rating: 2
There's quite a few different implementations of molecular memory. The one's I've read about generally have speeds comparable to DRAM, though with significantly lower power requirements and far higher bit densities. Some of them are nonvolatile, which would potentially position them to replace not only Flash Ram, but HDD storage as well.

RE: Good density, but what about performance?
By Cincybeck on 1/29/2007 8:34:48 PM , Rating: 1
Interesting. I would like to read more on the subject. I did a search on google and it returned millions of results. Do you have links on anything you recommend reading?

By masher2 on 1/30/2007 9:15:20 AM , Rating: 2
Try this PR material, from one of the major players in the field:

"Mac OS X is like living in a farmhouse in the country with no locks, and Windows is living in a house with bars on the windows in the bad part of town." -- Charlie Miller

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