
IBM creates 9nm carbon nanotube transistor that outperforms silicon - ukdm
http://www.extremetech.com/computing/115657-ibm-creates-9nm-carbon-nanotube-transistor-outperforms-silicon
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tpatke
When I think of IBM, I still think of consultants and guys in blue suits.
...but more than anyone else out there, these guys are building the future.

See also:

<http://en.wikipedia.org/wiki/Watson_(computer)>

[http://www.engadget.com/2011/06/30/embargo-ibm-develops-
inst...](http://www.engadget.com/2011/06/30/embargo-ibm-develops-
instantaneous-memory-100x-faster-than-fl/)

[http://www.engadget.com/2012/01/14/ibm-stores-bits-on-
arrays...](http://www.engadget.com/2012/01/14/ibm-stores-bits-on-arrays-of-
atoms-shrinks-magnetic-storage-to/)

I hate to think what their patent portfolio looks like.

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ginko
It's true that IBM does incredible research, but their results never seem to
break into mainstream.

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smackfu
I believe IBM was the first company to use GMR in hard drives.

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wazoox
And even hard drives, after all they invented them, too.

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ori_b
Transistors that outperform silicon aren't especially rare. The hard part is
finding ones that can be outmanufactured compared to silicon.

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wcoenen
How do they get the carbon nanotube in the correct position and orientation
like that? I suspect it will be difficult to do it reliably and cheaply for
billions of transistors at a time.

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johapers
I apologize if this is a bit long:

The answer can be found in the supplementary information to the article here:
[http://pubs.acs.org/doi/suppl/10.1021/nl203701g/suppl_file/n...](http://pubs.acs.org/doi/suppl/10.1021/nl203701g/suppl_file/nl203701g_si_001.pdf)

In short, they grew the nanotubes on a quarts crystal, transferred them with
tape quite randomly to gates already made on a Si-wafer and then etched and
metalized around these gates. They then tested a large amount of devices to
find ones where a nanotube of the right kind (semiconducting) had placed
itself in a correct alignment with the gate and metalized contacts (source and
drain). Once they knew what devices were working they imaged some of the
working devices with an Atomic Force Microscope (AFM) and did a bunch of
standard transistor measurements.

As was commented earlier, the specific growth of nanotubes in a well defined
position is not easily achieved. There is IMO a long time until anyone can do
a full chip where nanotubes grow exactly where one wants the transistors. It
might even be that graphene is a more convenient technology for just this
reason (since graphene can be grown somewhat more conveniently by annealing
SiC wafers). A side note I guess is that growing nanotubes and pillars
vertically can be done in specific spots on a wafer, but that makes
manufacturing of the gate a bit problematic. And I do not know wheter carbon
nanotubes can be grown selectively this way.

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kibwen
"At 9nm, IBM’s transistor is also smaller than the physical limit of silicon
transistors, which is around 11nm."

Can anyone cite a source for that statement regarding the theoretical minimum
size of silicon transistors?

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wcoenen
According to the Wikipedia article about the 11nm node, the thickness of the
gate dielectric becomes just 1 atom at that scale:
<http://en.wikipedia.org/wiki/11_nm>

~~~
Devilboy
Although Intel mentioned recently that they think they can make it to 8nm

