Images of the Racetrack chip show a single column of 40 nanowires, and close-ups of the wires.
Details of the first real-world test of a new memory chip technology have been revealed by IBM scientists.
The demonstration involved Racetrack memory - a system which stores information as magnetic patterns on tiny wires.
IBM said the technology promised faster data access speeds than were possible using hard drives or flash disks.
However it faces a challenge from other next-generation memory technologies being explored by other companies.
Speedy
The team - based in New York, California and Taiwan - has been working on the process since 2008.
The prototype chip consists of 256 Racetrack cells.
Each cell consisted of a single magnetic nanowire, 60-240 nanometres wide and 15-20 nanometres thick. A nanometre is a billionth of a metre.
Electric pulses are applied to the wires creating "domain walls" with "regions" between them.
These regions pass over a magnetic read/write head which faces them in one direction or another, representing the 0s and 1s of computer data.
The small magnetic regions can be "raced" at speed along the wires - giving the technique its name.
Advocates of Racetrack claim it could potentially read and write data hundreds of thousands of times faster than is possible on commercial hard disks.
That would put access speeds at roughly the rate offered by DRAM (Dynamic Random Access Memory) chips. These are already used in current PCs to run programs, but "forget" data as soon as the computers' power supplies are switched off.
"This breakthrough could lead to a new type of data-centric computing that allows massive amounts of stored information to be accessed in less than a billionth of a second," said a statement from IBM.
Long-lasting
The scientists noted that the circuitry involved was created using IBM's standard microchip-making technologies, highlighting its potential as a realistic replacement to existing memory storage techniques.
Racetrack may also prove more durable. IBM aims to create a device that can be wiped and rewritten millions of times. By contrast many flash memory drives can become unreliable after any single bit has endured about 100,000 writes.
However, the researchers acknowledge that more work needs to be done to optimise their process and improve "cell operation repeatability".
That means there is still time for Samsung, Hewlett Packard, Micron Technologies and other IBM researchers to complete work on alternative memory storage techniques that they hope will become future standards.
More details of the Racetrack technology are due to be discussed at the Institute of Electrical and Electronics Engineers' annual International Electron Devices meeting in Washington DC on Wednesday.
Wednesday, December 7, 2011
Silicon-free 'superior' Microchip
The researchers say molybdenite microchips would need less power than existing silicon-based circuits
The first computer chip made out of a substance described as a "promising" alternative to silicon has been tested by researchers.
The Switzerland-based team used molybdenite (MoS2) - a dark-coloured, naturally occurring mineral.
The group said the substance could be used in thinner layers than silicon, which is currently the most commonly used component in electronics.
It said MoS2 could make smaller, more flexible chips that used less energy.
The substance is currently used as an ingredient in engine lubricants, ski waxes and as a strengthening agent for plastics.
Prof Andras Kis, the director of the Laboratory of Nanoscale Electronics and Structures (LANES) in Lausanne, published details of the research in the latest edition of the ACS Nano journal.
He said the team chose to experiment with this semiconductor, rather than another material, in part because it was easily available.
"There is something like 19 million metric tonnes around," Prof Kis told the BBC.
"You can just go on some websites on the internet and buy a 1cm by 1cm crystal for around $100 [£64]."
Surfaces oxidise
To obtain a thin layer of the material to work with, Prof Kis's team put a strip of sticky plastic over the crystal, peeled it off and then attached the sliver to a support. The plastic was then peeled off to leave the very thin layer of MoS2 exposed.
Using this, the team built a prototype microchip circuit to which they attached up to six serial transistors allowing them to carry out simple logic operations.
The researchers say molybdenite crystals are relatively abundant in the natural environment
Although the integrated circuit was basic, Prof Kis said it proved that more complex designs would be possible on thinner chips than could be produced with silicon.
"The problem with silicon is that you cannot make very thin things from it because it is very reactive," he said.
"The surface likes to oxidise - to bind with oxygen and hydrogen - and that makes its electrical properties degrade when you want to make a very thin film."
As a result the thinnest usable layers of silicon used in computer chips have been around two nanometres thick. MoS2, by contrast, can be used in layers just three atoms thick, allowing chips to be made at least three times smaller.
Stiff as steel
A key advantage of having a thinner material is that the transistors can also be shrunk in size.
"If you have a transistor that is very thin it will also automatically dissipate less power - so it spends less power. So in a nutshell it allows you to make electronics that spend less electrical energy," Prof Kis said.
MoS2 also has the advantage that it is as stiff as stainless steel, but is also capable of being flexible.
Prof Kis says the material could help create flexible electronics that can be attached to skin
"It can be bent to large angles and can be stretched a lot," said Prof Kis.
"If you take a sheet of molybdenite you can stretch it so that it increases its length by 10% - that is a lot in this context.
"If you did the same with silicon it would break like glass."
The team said the material might be suitable for flexible electronics that could be rolled into tubes, attached to the skin or used to make mobile phones that curved themselves to fit the owner's face.
Low temperatures
MoS2 faces a challenge from graphene, another flexible semiconductor, as a potential replacement for silicon.
But the Swiss team believe their material has a key advantage - it can amplify electronic signals at room temperature, while graphene must be cooled to 70 Kelvin - cold enough for nitrogen to turn into liquid.
"If you look at the circuits in computers, for example, you have millions of transistors connected in series doing some kind of calculation," said Prof Kis.
"The important thing is that the signal that goes into the processor doesn't get reduced as a consequence of the operation, because then you'd lose your electrical signal in the chip.
"So it has to be constantly amplified. Silicon can do this and so can molybdenite, but graphene can only do it at very low temperatures."
Despite MoS2's potential, the researchers said it would be at least 10 to 20 years before it would be likely to enter commercial use.
In the meantime the group said it planned to explore whether it could make the mineral more conductive and would also try to find a less labour-intensive way of producing thin layers of the substance.
The first computer chip made out of a substance described as a "promising" alternative to silicon has been tested by researchers.
The Switzerland-based team used molybdenite (MoS2) - a dark-coloured, naturally occurring mineral.
The group said the substance could be used in thinner layers than silicon, which is currently the most commonly used component in electronics.
It said MoS2 could make smaller, more flexible chips that used less energy.
The substance is currently used as an ingredient in engine lubricants, ski waxes and as a strengthening agent for plastics.
Prof Andras Kis, the director of the Laboratory of Nanoscale Electronics and Structures (LANES) in Lausanne, published details of the research in the latest edition of the ACS Nano journal.
He said the team chose to experiment with this semiconductor, rather than another material, in part because it was easily available.
"There is something like 19 million metric tonnes around," Prof Kis told the BBC.
"You can just go on some websites on the internet and buy a 1cm by 1cm crystal for around $100 [£64]."
Surfaces oxidise
To obtain a thin layer of the material to work with, Prof Kis's team put a strip of sticky plastic over the crystal, peeled it off and then attached the sliver to a support. The plastic was then peeled off to leave the very thin layer of MoS2 exposed.
Using this, the team built a prototype microchip circuit to which they attached up to six serial transistors allowing them to carry out simple logic operations.
The researchers say molybdenite crystals are relatively abundant in the natural environment
Although the integrated circuit was basic, Prof Kis said it proved that more complex designs would be possible on thinner chips than could be produced with silicon.
"The problem with silicon is that you cannot make very thin things from it because it is very reactive," he said.
"The surface likes to oxidise - to bind with oxygen and hydrogen - and that makes its electrical properties degrade when you want to make a very thin film."
As a result the thinnest usable layers of silicon used in computer chips have been around two nanometres thick. MoS2, by contrast, can be used in layers just three atoms thick, allowing chips to be made at least three times smaller.
Stiff as steel
A key advantage of having a thinner material is that the transistors can also be shrunk in size.
"If you have a transistor that is very thin it will also automatically dissipate less power - so it spends less power. So in a nutshell it allows you to make electronics that spend less electrical energy," Prof Kis said.
MoS2 also has the advantage that it is as stiff as stainless steel, but is also capable of being flexible.
Prof Kis says the material could help create flexible electronics that can be attached to skin
"It can be bent to large angles and can be stretched a lot," said Prof Kis.
"If you take a sheet of molybdenite you can stretch it so that it increases its length by 10% - that is a lot in this context.
"If you did the same with silicon it would break like glass."
The team said the material might be suitable for flexible electronics that could be rolled into tubes, attached to the skin or used to make mobile phones that curved themselves to fit the owner's face.
Low temperatures
MoS2 faces a challenge from graphene, another flexible semiconductor, as a potential replacement for silicon.
But the Swiss team believe their material has a key advantage - it can amplify electronic signals at room temperature, while graphene must be cooled to 70 Kelvin - cold enough for nitrogen to turn into liquid.
"If you look at the circuits in computers, for example, you have millions of transistors connected in series doing some kind of calculation," said Prof Kis.
"The important thing is that the signal that goes into the processor doesn't get reduced as a consequence of the operation, because then you'd lose your electrical signal in the chip.
"So it has to be constantly amplified. Silicon can do this and so can molybdenite, but graphene can only do it at very low temperatures."
Despite MoS2's potential, the researchers said it would be at least 10 to 20 years before it would be likely to enter commercial use.
In the meantime the group said it planned to explore whether it could make the mineral more conductive and would also try to find a less labour-intensive way of producing thin layers of the substance.
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