• Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.
  • The forums have been upgraded with support for dark mode. By default it will follow the setting on your system/browser. You may override it by scrolling to the end of the page and clicking the gears icon.

First computer made of carbonnanotubes is unveiled

Joined
Mar 26, 2010
Messages
9,925 (1.79/day)
Location
Jakarta, Indonesia
System Name micropage7
Processor Intel Xeon X3470
Motherboard Gigabyte Technology Co. Ltd. P55A-UD3R (Socket 1156)
Cooling Enermax ETS-T40F
Memory Samsung 8.00GB Dual-Channel DDR3
Video Card(s) NVIDIA Quadro FX 1800
Storage V-GEN03AS18EU120GB, Seagate 2 x 1TB and Seagate 4TB
Display(s) Samsung 21 inch LCD Wide Screen
Case Icute Super 18
Audio Device(s) Auzentech X-Fi Forte
Power Supply Silverstone 600 Watt
Mouse Logitech G502
Keyboard Sades Excalibur + Taihao keycaps
Software Win 7 64-bit
Benchmark Scores Classified
The first computer built entirely with
carbon nanotubes has been unveiled,
opening the door to a new generation of
digital devices.

_70097569_maxshulaker_039.jpg


"Cedric" is only a basic prototype but could be
developed into a machine which is smaller,
faster and more efficient than today's silicon
models.
Nanotubes have long been touted as the heir to
silicon's throne, but building a working computer
has proven awkward.
The breakthrough by Stanford University
engineers is published in Nature .
Cedric is the most complex carbon-based
electronic system yet realised.
So is it fast? Not at all. It might have been in
1955.
The computer operates on just one bit of
information, and can only count to 32.
"In human terms, Cedric can count on his hands
and sort the alphabet. But he is, in the full sense
of the word, a computer," says co-author Max
Shulaker.
"There is no limit to the tasks it can perform,
given enough memory".
In computing parlance, Cedric is "Turing
complete". In principle, it could be used to solve
any computational problem.
It runs a basic operating system which allows it
to swap back and forth between two tasks - for
instance, counting and sorting numbers.
And unlike previous carbon-based computers,
Cedric gets the answer right every time.
Imperfection-immune
"People have been talking about a new era of
carbon nanotube electronics, but there have
been few demonstrations. Here is the proof,"
said Prof Subhasish Mitra, lead author on the
study.
The Stanford team hope their achievement will
galvanise efforts to find a commercial successor
to silicon chips, which could soon encounter
their physical limits.

Carbon nanotubes (CNTs) are hollow cylinders
composed of a single sheet of carbon atoms.
They have exceptional properties which make
them ideal as a semiconductor material for
building transistors, the on-off switches at the
heart of electronics.
For starters, CNTs are so thin - thousands could
fit side-by-side in a human hair - that it takes
very little energy to switch them off.
"Think of it as stepping on a garden hose. The
thinner the pipe, the easier it is to shut off the
flow," said HS Philip Wong, co-author on the
study.
But while single-nanotube transistors have been
around for 15 years, no-one had ever put the
jigsaw pieces together to make a useful
computing device.
So how did the Stanford team succeed where
others failed? By overcoming two common
bugbears which have bedevilled carbon
computing.
First, CNTs do not grow in neat, parallel lines.
"When you try and line them up on a wafer, you
get a bowl of noodles," says Mitra.
The Stanford team built chips with CNTs which
are 99.5% aligned - and designed a clever
algorithm to bypass the remaining 0.5% which
are askew.
They also eliminated a second type of
imperfection - "metallic" CNTs - a small fraction
of which always conduct electricity, instead of
acting like semiconductors that can be switched
off.
To expunge these rogue elements, the team
switched off all the "good" CNTs, then pumped
the remaining "bad" ones full of electricity - until
they vaporised. The result is a functioning circuit.
The Stanford team call their two-pronged
technique "imperfection-immune design". Its
greatest trick? You don't even have to know
where the imperfections lie - you just "zap" the
whole thing.

"These are initial necessary steps in taking
carbon nanotubes from the chemistry lab to a
real environment," said Supratik Guha, director
of physical sciences for IBM's Thomas J Watson
Research Center.
But hang on - what if, say, Intel, or another chip
company, called up and said "I want a billion of
these". Could Cedric be scaled up and factory-
produced?
In principle, yes: "There is no roadblock", says
Franz Kreupl, of the Technical University of
Munich in Germany.

_70098463_handholdingcntwafer_008.jpg

"If research efforts are focused towards a
scaled-up (64-bit) and scaled-down (20-
nanometre transistor) version of this computer,
we might soon be able to type on one."
Shrinking the transistors is the next challenge for
the Stanford team. At a width of eight microns
(8,000 nanometres) they are much fatter than
today's most advanced silicon chips .
But while it may take a few years to achieve this
gold standard, it is now only a matter of time -
there is no technological barrier, says Shulaker.
"In terms of size, IBM has already demonstrated
a nine-nanometre CNT transistor.
"And as for manufacturing, our design is
compatible with current industry processes. We
used the same tools as Intel, Samsung or
whoever.
"So the billions of dollars invested into silicon
has not been wasted, and can be applied for
CNTs."
For 40 years we have been predicting the end of
silicon. Perhaps that end is now in sight.



http://m.bbc.co.uk/news/science-environment-24232896
 
How this is any better than silicon transistors for future processors? I thought the fundamental problem with process advancement was that, even neglecting leakage, you can't build a transistor smaller than a few atoms. Within 10-15 years a transistor will be made up of fewer than 10 atoms. It doesn't seem like CNTs are any more space efficient than silicon transistors and this problem with shrinking feature sizes will still exist.

Edit: I reread the article and it refers to CNTs being able to increase switching speed compared to silicon transistors, which would improve performance. But my prior statement still applies, you can't keep shrinking silicon transistors or CNTs indefinitely. The CNT research needs to focus on continuing to increase CNT switching speed at the same time as reducing feature size or else that technology will hit a performance limit around the same time silicon does.

What I interpret needing to be done within the next 15-20 years to continue increasing performance exponentially is a fundamental change in the method of computation where binary is no longer used, be it quantum computing, DNA computing, or some other technology.
 
Last edited:
Can it run Crysis?......................Sorry someone had to.

Interesting, maybe silicons days are numbered
 
We need to overclock it to see its potential.
 
Back
Top