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Buckminsterfullerene Strikes Again - Nanotube RAM
putaro writes "Nanotube based RAM, under development by Nantero, promises to deliver densities of over 1 terabit per cm^2, is non-volatile and faster than current DRAM. The Economist has a nice story. Forget about just kicking DRAM's and FLASH's butt, is this finally the end of magnetic storage as well?"
A new type of computer memory uses carbon, rather than silicon
WAITING for a computer to turn on is a nuisance. That is why manufacturers have been trying to create "non-volatile" memories. These would be fast, like the random-access memory (RAM) chips that are currently used for often-accessed memory, but they would also continue to store information even without power, like hard drives, which are too slow to use except for long-term storage.
Several technologies have been competing to become the standard for fast, non-volatile memory. The best known is magnetic RAM, which IBM and Motorola are touting. Others are based on polymers or on strange-sounding metal alloys called chalcogenides that change shape when an electric charge is applied to them. But there is now a new entrant to the field: carbon.
Carbon comes in many forms. Diamonds and graphite are two of the most familiar ones. A less familiar variety is the nanotube, also known as a "buckytube" after Richard Buckminster Fuller, whose geodesic domes have a framework similar to the arrangement of the atoms in a nanotube. Nanotubes consist of a cylindrical array of carbon atoms whose diameter is only about 1 nanometre (a billionth of a metre). If Nantero, a firm based in Woburn, Massachusetts, proves correct, such tubes will soon be an integral part of computer memories.
Nantero's memory chips consist of billions of nanotubes, each a few hundred nanometres long, suspended from a silicon wafer. Another wafer sits about 100 nanometres below the first. Because the nanotubes that Nantero uses conduct electricity, a small electric charge at one point on the second wafer will draw several dozen nanotubes towards it. Once they are there, they stay there. That is because they are bound by Van der Waals forces--intermolecular bonds that do not depend on external power for their maintenance. An additional application of current, however, will release the nanotubes. This means that a group of a few dozen nanotubes can act as a memory element, storing a single bit (either a one or a zero) of the binary code that computers use to operate. If the connection between the wafers is live at a particular point, the bit represented is a one. If not, it is a zero.
If nanotubes were not so small, this would not be a big deal. Because they are, though, Nantero's technology can already achieve a data density considerably higher than existing RAMs. And because the wafers are so close together, those data can move rapidly from place to place. Nantero's new memory can read or write a bit in as little as half a nanosecond (billionth of a second). The best RAM chips, by contrast, need ten nanoseconds to perform a similar operation.
At the moment, Nantero has only a working prototype. But the firm aims to have memories on the market within a year. It thinks it will be able to tool up for commercial production quickly, because the fabrication technique it uses, though novel, relies on standard semiconductor-making technology.
The main difficulty faced by others who have tried to go down the buckytube route is getting the tubes to align with each other when they are hung from the first wafer. Until now, the approach has been to try to grow all of the tubes in the correct orientation to start with. But Nantero's founders came up with a simpler, if less elegant, solution. They use established lithographic techniques to get rid of tubes that are pointing in the wrong direction by zapping them with an electron beam. That leaves only those that are hanging down towards the opposite wafer.
Though the recent chip is certainly impressive, the reason for getting excited about Nantero is not so much the present as the future. Unlike silicon, which is pushing against its physical limitations, carbon-nanotube technology is in its infancy. Greg Schmergel, Nantero's boss, says that within the next few years the firm's engineers may be able to achieve data densities of a trillion bits per square centimetre (more than 1,000 times that available on existing RAM) and it will be possible to read those memories 100 times faster than can be done at the moment. The days of silicon-based memory may be numbered
Here's a little details that pretty much summarize the docs:
How it works. Nantero's memory chips consist of billions of nanotubes, each a few hundred nanometres long, suspended from a silicon wafer. ... This means that a group of a few dozen nanotubes can act as a memory element, storing a single bit (either a one or a zero) of the binary code that computers use to operate. If the connection between the wafers is live at a particular point, the bit represented is a one. If not, it is a zero.
Speed. Nantero's new memory can read or write a bit in as little as half a nanosecond.
Availability. At the moment, Nantero has only a working prototype. But the firm aims to have memories on the market within a year.
Hurdles. The main difficulty faced by others who have tried to go down the buckytube route is getting the tubes to align with each other when they are hung from the first wafer. Until now, the approach has been to try to grow all of the tubes in the correct orientation to start with. But Nantero's founders came up with a simpler, if less elegant, solution. They use established lithographic techniques to get rid of tubes that are pointing in the wrong direction by zapping them with an electron beam. That leaves only those that are hanging down towards the opposite wafer.
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Error 500: Internal sig error
I guess it means lots of space (for data) in a small amount of (spatial) space. 120something GB in the space of your thumbnail.
For those who are interested, the Nantero's technology is based on earlier work in the lab of Charles M. Lieber. The original paper was published in the journal Science. Rueckes et al, Science, Vol 289, P. 94. Rueckes went on to found Nantero.
The original experiment worked as follows:
The original experiment was done with bundles of carbon nanotubes. In principle, the concept should work at much higher densities for single nanotubes, but the technology still has hurdles to cross. Currently, the tubes conduct because ropes of tubes are likely to contain both semiconductor type and metal type tubes. Since metal type tubes are fantastic conductors, having even a few of them in a rope will allow a device to work. However, when one crosses the threshold to single nanotubes, the device will only work if the tubes are metal type. Hence, an important problem will be finding a way to produce only metal type single walled nanotubes. Currently, carbon nanotubes are produced in a mixture of semiconductor type and metal type nanotubes. It's difficult to control that property because it depends sensitively on the way the sp2 bonds on the nanotube sidewall line up, something that no one yet knows how to control.
This is how big their protoptype is from their website:
"Dr. Thomas Rueckes, Chief Scientific Officer
and Co-Founder said, "This gets around
the problem that nanotubes cannot reliably be
grown in large arrays. At the end of our
process only the nanotubes in the correct
positions are remaining. This process was
used to make a 10Gb array now, but could easily
be used to make even larger arrays--
the main variable now controlling the size is the
resolution of the lithography equipment."
well... if your name is minime disregard this ;-)
In Canada, we don't fancy things like socks
Your can count on absolutely ZERO security if people have physical access to your machine.
Use whatever encryption or security precautions you like. At the very least, a keyboard sniffer can easily compromise the enitre system.
This technology changes nothing.
That's funny, I always thought that the clock speed was the frequency at which a crystal oscillated.
It's got nothing to do with 'the longest segment of the pipe'
And it always will be...
Banaaaana!
Being at the school that discovered the flashy nano-tubes, I have had first hand experience with information regarding these. There are different arrangements of nano-tubes. Most nano-tubes are extremely stable, that is, are strong and chemically non-reactive, etc. The nano-tubes that burn when exposed to a flash do so because they are not of the more common variety. In the report, the researcher explained that he had taken a different approach to harvesting the nano-tubes, and this approach yielded different nano-tubes, ones that weren't as stable as the rest...
This is a static and nonvolatile technology. Think of a CPU that can be dynamically switched to zero hz while keeping its state - a complete machine that can be frozen and reawakened in an instant.
If you have the memory structure, why not have 256 bit parallel data paths? Or, why not have megabytes of fast memory right on the CPU die? Or arrays of fast CPUs, each with (say) half a gig of fast nonvolatile (ahem) "cache?"
Anyone remember "Transputer?"
From the description it should be as easy to make an AND or OR gate as it is to make a flipflop, since each nanotube is just a switch. Seems logical there are far deeper applications for this than just memory arrays. Or, since the speed and density are both there, perhaps a doorway to fast associative arrays?
Actually for most peoples desktop machines S-ATA and Ultra 320 SCSI are faster than their PCI busses (33Mhz-32bit PCI is only 133MB/s). Besides, who cares if the bottleneck moves to the physical connection, at least it is away from the slow arse hdd's of today (8+ms access time and slow max transfer vs .5ns access and fast as your bus can handle transfer). I would upgrade in a heartbeat. Plus removing on of the last important physical device would do wonders for improving the reliability of computers (the cpu and case fans are still there). To get the most out of this you might need to redesign things, but I would be willing to bet that the first uses are for retrofits, market inertia tends to work that way.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Okay Jr. sit down and let's have a talk. Ya see son, that P4 super whiz bang game machine you're sitting at right now has a clock speed of 66Mhz. Yup, no kiddin. What them ol wizards up at Intel done did is ta multiply the clock. Pretty tricky eh? That's why they get the big bucks.
What this article was talking about when it used the word "speed" wasn't an arbitrary marketing gimmick like "clock speed" to sell overheated toys to kids like you but the speed of the data refresh.
SRAM like you have in your P4 super game machine as cache currently can refresh at 10ns. This stuff would blow your quote 3Ghz Intel machine out of the water.
A fullerene is a certain class of carbon molecules that have a tubular or spherical form. The Buckminsterfullerene, or "buckyball" refers to the specific spherical C60 fullerine (shaped like a football). All other non spherical molecules (eg tubular) are just referred to as fullerenes.
Well, I don't think so, actually.
/forever/. This is just one example, there are *many* more, independent of operating system (I'm unfortunately forced to use Windows for work).
You still need a bootstrap that will go reset the memory and restart the OS.
If you don't, what's going to happen is that some bug is going to manifest itself, and it's never going to go away because you have no method resetting it - if you turn the machine off, then on, the messed up driver (or whatever) comes back in exactly the same bogus state.
Think about it. I've seen bad net (VPN) drivers for windows cause my normal networking drivers to be very slow once the vpn comes down, the only cure being a restart (when it happens, which is not often).
So now, with, as you say, the death of the concept of bootstrapping, when that happens, I'd have to live with slow network drivers
You will still need the 'entire concept of bootstrapping', even if only as a cure to some other guys kernel-space bugs.
Code or be coded.