Graphene Transistor Speed Record

[CraigS]

Now here's one worthwhile noting … (even though not strictly Astronomy .. but for processing those AP images ...):

"Graphene transistor beats speed records" (http://physicsworld.com/cws/article/news/43668)



They are going on to fabricate transistors that push the cutoff frequency towards 1 THz !

Watch this space ... this one is going to be big … I mean ...really big !

Cheers

[renormalised]

A few more years and if they bring this out commercially, it will revolutionise the computer industry, for sure!!!.

[bojan]

Don't hold your breath just yet...
The beta of those transistors are still very low.. lower than 1 actually. Those guys just demonstrated that Graphene could be used ....
But before those transistors become really useful. they need to have gain at least 10.
And, they must be cheaper to manufacture...
So, before that happens... we still have silicon and GaAs (for 300GHz and up).

What will REALLY revolutionise the computer industry one day will be parallel processing (in other words: software. We still do not have proper compilers that can produce reliable code for more that 4 cores).. otherwise with graphene processors we will only have 1000x bigger and equally unreliable and slow windows OS or equivalent, just what we have today.

[CraigS]

The transconductance of a MOSFET decides its gain. In currently available technologies, as you reduce the size of the MOSFET, the transconductance is reduced because dopant impurity starts to impact on electron mobility.

So, seeing as native graphene devices have two orders of magnitude higher mobility than Si or GaAs devices, I'd say there's pretty reasonable potential for tradeoffs when it comes to gain.
Anyway, for digital switching applications all you need is on/off. I'm not so sure analogue applications are where the playing field is (hence the gain may not be the primary factor). Speed is the primary performance criteria for digital switching apps, and reduced heating (due to resistance).


Agreed. But the graphene transistors are now in the ballpark and orders of magnitude better in switching performance up to 300GHz. (That limit will improve .. it always has .. Moore's Law) (http://en.wikipedia.org/wiki/Moore%27s_law).


This software is required no matter what technology substrate you use.
The real revolution will be quantum computing. That's further out though .. and graphene substrate will be available in shorter timeframes. Not sure what they'll run quantum computing on .. it seems to be intrinsically linked with photonics developments.


I'm not sure I get the 100x bigger ??

Cheers
PS: Good to hear from you on this one, Bojan. :)

[bojan]

By 100x bigger I meant 100x larger in amount of memory and speed requirements, both HD and RAM (yes, 1000x more features.. But at the end of the day, PC will again need couple of minutes to wake up, and the operator will still have to wait for computer, and not the other way around. And this will be only because the higher speed will allow larger OS.. End result is still the user frustration)

What I am trying to say, it is not the HW that is limiting the performance of today's computers - transputers (http://en.wikipedia.org/wiki/Transputer) were available on the market 20y ago, but noone knew how to use them properly (lack of compilers).. so they sort of disappeared, to be replaced by easier to use and faster processors.. faster but still just Von Neumann concept.

Perhaps the lack of competition is partly to blame (essentially only one OS and only one processor manufacturer dominating the market... I don't want to mention names here :-)

[CraigS]

Interestingly, it seems that the transputer was employed in the High Energy Transient Explorer (http://en.wikipedia.org/wiki/High_Energy_Transient_Explorer) spacecraft observatory, launched in 1996 and then again in 2000, which then led to the discovery of several Gamma Ray Bursts.

Also, as you indicate, the success of technology developments thesedays may be dependent on who is doing, (or funding), the research. It seems that companies like IBM are presently behind graphene transistor technology. I'll keep an eye out for others .. if Intel gets into it, I'd bet it would take off.

There is always a need for faster, more energy efficient hardware processor technologies. By this, I'm talking about the limitations stemming from the physics of the base materials used in the chips themselves. As I mentioned previously, it would seem that Si and GaAs MOSFETs are pushing the basic limitations in the physical parameters (ie: transconductance).

The transputer concept seems to have been about architectural changes in the design of microprocessor (CPU) chips (and also, as you say, matching this to the OS/software). The chips were still designed on the standard base (substrate) materials of the day. Graphene is a new base substrate material, which posesses unique abilities at the transistor level, which would ulitmately permit re-architecture of CPU design, along the same lines as the transputer concept, if anyone ever chooses to have a go at this.

The introduction of Graphene base transistors represents a pure shift in the technology basis of all chips … CPU, logic, etc. This shift is to a large certain extent, independent of CPU and software architectures which would re-evolve to exploit the basic physics hurdles, overcome at the electron etc level.

To me, this is the definition of a pure 'Technology Shift' and is very much distinct from 'Re-Architecture' or redesign.

Cheers & Rgds.

[CraigS]

Bojan (& others):

Here you go … a couple of updates on Graphene Technologies:
Graphene single-transistor amplifier is a first (http://physicsworld.com/cws/article/news/44089), Oct 21st:


and then (Sept 23rd) ..

Graphene makes 'supercapacitor' (http://physicsworld.com/cws/article/news/43828)


Graphene is also very closely related to the 'BuckeyBalls' (found in space this year .. that's just for the Astronomers out there :) )

Cheers

[Omaroo]

http://www.mit.edu/newsoffice/2011/graphene-thermoelectric-1007.html

Looks promising now in direct reference to sensors that like the infra-red...

[Poita]

There seems to be an endless amount of graphene news over the last 5 years or so, always promising some major change to the way the world works, but no products yet.
I'm hoping some come to fruition sometime soon, I was so excited by graphene a few years ago, but gave up following it a while back. Hopefully some actual products are much closer to release now.

[Poita]

I worked on the OS for the Atari Transputer project.. yes, Atari of all people designed a working Transputer all those years ago, and yes, the major challenge was harnessing the power.