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Graphene May be the New Silicon

ScuttleMonkey posted more than 6 years ago | from the bouncing-off-walls dept.

Hardware 115

esocid writes to share that University of Maryland physicists have demonstrated that the material of the future may be graphene rather than silicon. Electricity conduction through graphene is about 100 times greater than that of silicon and could offer many improvements to things like computer chips and biochemical sensors. "Graphene, a single-atom-thick sheet of graphite, is a new material which combines aspects of semiconductors and metals. [...] A team of researchers led by physics professor Michael S. Fuhrer of the university's Center for Nanophysics and Advanced Materials, and the Maryland NanoCenter said the findings are the first measurement of the effect of thermal vibrations on the conduction of electrons in graphene, and show that thermal vibrations have an extraordinarily small effect on the electrons in graphene."

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The "100 times greater"... (5, Interesting)

26199 (577806) | more than 6 years ago | (#22850836)

...refers to electron mobility [wikipedia.org] , a concept I hadn't previously encountered. But it's easy enough to understand: if I apply a unit electric field to a material, how fast does it make the electrons drift? This is the mobility.

Apparently graphene (also new to me ... a single-atom layer of carbon) is exciting because it has much higher electron mobility than silicon. Which leads to faster switching times, although they don't explain that part.

All this seems to be theoretical at the moment, due to insufficiently pure graphene. Still, 100th the switching delay is not a bad target to be aiming at... 100Ghz processing!

Re:The "100 times greater"... (1)

Arccot (1115809) | more than 6 years ago | (#22850868)

...refers to electron mobility [wikipedia.org] , a concept I hadn't previously encountered. But it's easy enough to understand: if I apply a unit electric field to a material, how fast does it make the electrons drift? This is the mobility.

Apparently graphene (also new to me ... a single-atom layer of carbon) is exciting because it has much higher electron mobility than silicon. Which leads to faster switching times, although they don't explain that part.

All this seems to be theoretical at the moment, due to insufficiently pure graphene. Still, 100th the switching delay is not a bad target to be aiming at... 100Ghz processing!

Thanks, now I don't have to RTFA. I was wondering why pure conductivity improvements are good for gates. Semiconductors are used for a reason. :-)

Re:The "100 times greater"... (1, Funny)

Anonymous Coward | more than 6 years ago | (#22850942)

I was wondering why pure conductivity improvements are good for gates. Semiconductors are used for a reason. :-)
Not only that, graphene breast implants are totally risk free!

Re:The "100 times greater"... (2, Funny)

maxume (22995) | more than 6 years ago | (#22851032)

It would have been a lot funnier to have said 'graphite' there.

Re:The "100 times greater"... (4, Interesting)

Btarlinian (922732) | more than 6 years ago | (#22851656)

Thanks, now I don't have to RTFA. I was wondering why pure conductivity improvements are good for gates. Semiconductors are used for a reason. :-)

The increased mobility has little to do with gates. In fact, you want gates (in MOSFETs [wikpedia.org] ) to be as resistive as possible, but still not attenuate the electric field that results from the gate voltage, hence the use of Halfnium dioixde instead of silicon dioxide (you can make it thicker, (and thus more resistive) while still having a strong enough field.)

Mobility results from the equation v=(mu)E, where mu is the mobility and v is the velocity of an charge carrier (electron or hole) The reason we use semiconductors is that we can easily control the number of electrons or holes. But by increasing the speed of electrons, we can allow them to switch faster since they will be able to cross the channel more quickly. That's why smaller transistors can switch more quickly, the channel length is shorter so it takes less time for carriers to traverse them.

I'm not sure why it's considered so amazing to discover that graphene has a good electron mobility. Since, the entire structure consists of delocalized pi orbitals, you would expect electrons to easily travel through graphene. I'm not sure how graphene would be doped either. I suppose you could use boron and phosphorous like in silicon, but it remains to see if they will still bond appropriately. Ah well, there's a reason, they're professors and I'm a student.

Re:The "100 times greater"... (1)

osu-neko (2604) | more than 6 years ago | (#22851942)

I'm not sure why it's considered so amazing to discover...

Science writing is frustrating if you know anything at all about what's being discussed. It's dumbed down to the point that you feel less informed for having read it. They invariably leave out the "trivial" little detail that makes it all make sense. They might as well just write, "Something new and nifty and important has been discovered! But it's too complicated to explain it to you, so we'll spare you the boring, complicated details."

Re:The "100 times greater"... (5, Funny)

thrillseeker (518224) | more than 6 years ago | (#22852336)

"Something new and nifty and important has been discovered! But it's too complicated to explain it to you, so we'll spare you the boring, complicated details."

Your in-depth analysis intrigues me, and I wish to subscribe to your newsletter.

Question about "holes" (2, Interesting)

GPS Pilot (3683) | more than 6 years ago | (#22853578)

As I understand it, a "hole" is just the absence of an electron, which leads to a net positive charge for a particular atom. Kind of like a positive ion, but I think use of the term "ion" is limited to liquid solutions/gases/plasmas.

An electron can move and fill a hole, but leaves another hole behind in the location it just departed. So a "hole" moving in one direction is entirely equivalent to an electron moving in the opposite direction, is it not?

If so, why does this term have any usefulness, if, instead of saying "the hole moved from point A to point B" you could just as easily say "the electron moved from point B to point A"?

Help me understand why much ado is made about holes.

Re:Question about "holes" (1)

Pikoro (844299) | more than 6 years ago | (#22853978)

This being slashdot, I doubt you'll get an answer as to "why much ado is made about holes" from this crowd :)

Re:Question about "holes" (3, Informative)

error_logic (1160341) | more than 6 years ago | (#22854046)

Representing charge as "holes" is useful for current said to be flowing from a higher voltage (lacking electrons) to a lower voltage. The electrons are actually going from where they are in excess (giving a more negative charge) to where they are lacking. Therefore, the "holes" and electrons are trading places. It's like heat being dissipated, and saying "cold" is moving in.

The way you describe the motion of electrons and holes as being equivalent but in opposite directions is a very good way to look at it; both are valid, and used interchangeably based on the situation.

(Insert Standard Flow vs. Conventional Flow rant here)

Re:The "100 times greater"... (1)

KDR_11k (778916) | more than 6 years ago | (#22855558)

Would mobility be useful for making wires transmit data faster or is that something else again?

Re:The "100 times greater"... (1)

mrbluze (1034940) | more than 6 years ago | (#22850870)

How can Graphene be the new silicon if it's just one atom thick. I don't think we're likely to be seeing Graphene enhancements on our girlie Jpegs and AVI's anytime soon.

Re:The "100 times greater"... (4, Funny)

26199 (577806) | more than 6 years ago | (#22850896)

I think you mean silicone.

The "e" is very important. (As the raver said to the priest).

Re:The "100 times greater"... (5, Funny)

mrbluze (1034940) | more than 6 years ago | (#22850976)

I think you mean silicone.
Okay then, Graphenee boobs then.

Re:The "100 times greater"... (1)

Jugalator (259273) | more than 6 years ago | (#22851442)

I'm just waiting for Rule 34 to kick in any minute now.

negligable thickness -- (1)

Joseph_Daniel_Zukige (807773) | more than 6 years ago | (#22851012)

Maybe it makes a great negligee?

I know, I know, a different enhancement problem set from the target of silicone [wikipedia.org] enhancements. But I prefer the more natural sort of enhancement, myself.

But the health issues of silicone and asbestos and the like do raise a question to me about graphene and other carbon filament materials.

OT: Re: Sig (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22850940)

f8d > xkcd ?

I'm going to say... no. I read a bunch of them and it just doesn't have the genius spark xkcd has. The art is horrid. While xkcd seems to have a style to it, f8d looks like that's just being used because someone tried to "pretty up" stick figures. Some of the xkcd stuff, especially the early stuff, shows that he really can draw. I didn't get that sense from f8d.

None of the comics I read made me laugh. There was a "huh... that's kinda cute" about some of them though.

I'd say if you think f8d is better, then you just don't get xkcd. Some people don't. I've shown it to people and they have no idea why it would be funny.

It's either a very pale imitation of xkcd, or nothing like it and the comparison just does them both a disservice.

Re:OT: Re: Sig (0, Troll)

shadow349 (1034412) | more than 6 years ago | (#22851006)

Web comic strips are about as funny as blog "journalism" is credible.

Re:OT: Re: Sig (0)

Anonymous Coward | more than 6 years ago | (#22851114)

Thanks for answering :)

I don't think f8d beats xkcd at being xkcd ... that would be silly. xkcd wins at being xkcd, and is one of my favourite webcomics.

So really the comparison is kinda pointless. But it's noticable, and so makes a good sig :)

Re:The "100 times greater"... (1)

Falstius (963333) | more than 6 years ago | (#22850986)

Silicon is the material of choice because of its good oxide and because engineers have, what, 60 years of experience with it now? Limits to scaling down silicon based chips come from silicon oxide not being a good enough dielectric (insulator) and from very small 'off' transistors letting through too much leakage current. More conductive materials aren't particularly helpful in that regard.

Polycrystal silicon is used for transistor gates and routing signals over very short distances, maybe they mean to replace that with graphene?

Haven't RTFA, someone who has should enlighten us lazy posters if this detail is there.

Re:The "100 times greater"... (1)

misleb (129952) | more than 6 years ago | (#22851640)

Does "higher electron mobility" necessarily mean more conductive in the "off" state? I thought it just meant faster switching.

Re:The "100 times greater"... (1)

Falstius (963333) | more than 6 years ago | (#22852086)

Does "higher electron mobility" necessarily mean more conductive in the "off" state? I thought it just meant faster switching.

I was just pointing out that it doesn't address the significant problems in current devices. I don't think it will significantly affect either if it were used as a replacement semiconductor (if it even could be used that way). When materials like carbon nanotubes are made into 'transistors' the device changes significantly and generally works on different principles that current devices, so what holds for silicon transistors goes out the window.

Re:The "100 times greater"... (5, Interesting)

wass (72082) | more than 6 years ago | (#22851046)

Graphene has been studied for a few years now, even longer if you count it as rolled into a nanotube.

What took awhile (and was solved with a fairly low-tech solution : scotch tape) was how to make a single layer of graphene to measure, whereas graphite usually rolled off into multi-layer pieces.

Graphene is interesting for a number of reasons. Primarily is it's Minkowski lightcone-like density of states. The Fermi level lies right at the cone vertex, which makes this material a "zero-bandgap insulator", which brings about a huge number of interesting properties in itself.

Anyway, graphene has been hugely popular in condensed matter physics for a few years now, and people have studied the phonon spectra, I remember going to a seminar about the modes of graphene in a carbon nanotube a few years ago.

However, don't get your hopes up for mass-produced graphene tech anytime soon. While people will probably demonstrate small-scale single-electron transistors or other interesting graphene devices (if they haven't already), the ability to deposit and pattern graphene is still very crude, and it's hard to do anything other than one-off devices at this point.

Re:The "100 times greater"... (2, Interesting)

mapsjanhere (1130359) | more than 6 years ago | (#22851300)

It's also very hard to "solder" interconnects on a single layer sheet. Alnd, due to the 2 dimensional nature of the graphene sheet you can't easily take advantage of modern multilayer silicone processing. Making a true device from this will be challenging.

Re:The "100 times greater"... (0)

Anonymous Coward | more than 6 years ago | (#22852364)

That's why they should alternate layers of graphene with one-atom-thick layers of other elements.

Guess what you call that? That's right... a NANO-SANDWICH.

Thank you! I'll be here all week!

(mom says I'm grounded and have to stay in the basement)

Re:The "100 times greater"... (1, Funny)

commodoresloat (172735) | more than 6 years ago | (#22851326)

Graphene has been studied for a few years now, even longer if you count it as rolled into a nanotube.
So the internet will soon be a series of nanotubes?

Re:The "100 times greater"... (1)

wass (72082) | more than 6 years ago | (#22851370)

So the internet will soon be a series of nanotubes?

No, by that time it will more closely resemble a large truck.

Re:The "100 times greater"... (1)

discontinuity (792010) | more than 6 years ago | (#22851826)

What took awhile (and was solved with a fairly low-tech solution : scotch tape) was how to make a single layer of graphene to measure, whereas graphite usually rolled off into multi-layer pieces.

There also is a group investigating this at Georgia Tech: http://www.physics.gatech.edu/npeg/index.html [gatech.edu] (site has a halfway-decent FAQ for those not familiar with graphene).

I met one of the students from the GT group recently and he mentioned the scotch tape solution and said he said his lab were investigating how to manufacture the material practically. For all it's promise, I got the impression that two or three major breakthroughs were needed to make it viable. It's definitely a few years away. (I mean, they're not even up to duct tape yet!)

Re:The "100 times greater"... (1)

neurolux (1150083) | more than 6 years ago | (#22854434)

If it's just a single layer of graphite, why don't they just draw the tiny circuits with a pencil on tiny pieces of paper. That'll do the same thing right?

Re:The "100 times greater"... (3, Interesting)

DigiShaman (671371) | more than 6 years ago | (#22851074)

I remember reading about how physicists are running into the limitations of "C" (speed of light) with regards to signal propagation across the CPU die. Even though something measuring 143 mm^2 is small, at speeds of 100GHz (or was that 1Thz), I doubt your processing can remain symmetrical. If that's true, such fast CPUs will need to be engineered for asymmetrical processing instead.

Re:The "100 times greater"... (3, Interesting)

Cecil (37810) | more than 6 years ago | (#22851350)

On the other side of the coin, the design for an original Pentium had around 5 million transistors. Modern processors have more like 300 million. What's changed? Well, dual-core, and 64-bit, sure. But a lot of those extra transistors are to create extra pipelines or additional specialized instructions or even specialized pipelines that only run specialized instructions to compensate for the fact that the clock speeds just won't ramp up as quickly as designers want. Perhaps if we were able to start cranking up the clock speeds again, it would be possible to start streamlining those pipelines and instruction sets into something more manageable for keeping your signals properly synchronized.

Re:The "100 times greater"... (4, Informative)

cyfer2000 (548592) | more than 6 years ago | (#22851940)

Cache, bloody huge cache. 6 transistors per bit, 48 per byte, 49152 per KiB, 50,331,648 per MiB. If you have 4 MiB cache, it's 201,326,592 transistors.

Re:The "100 times greater"... (2)

Cecil (37810) | more than 6 years ago | (#22853262)

Thanks for the info. If I hadn't already posted I'd vote you up informative, but since I have, I'll have to settle for telling you you're informative instead.

Seriously though, thanks, I didn't realize that moving to on-die cache would've made such a drastic difference in transistor count. Very interesting.

Re:The "100 times greater"... (0)

Anonymous Coward | more than 6 years ago | (#22853152)

But a lot of those extra transistors are to create extra pipelines or additional specialized instructions or even specialized pipelines that only run specialized instructions to compensate for the fact that the clock speeds just won't ramp up as quickly as designers want.
No, the problem is that the clock speed on the CPU ramps up too quickly compared to the speed of the memory bus. You can run a CPU with a large multiplier, but the faster it goes, the more time the CPU will spend waiting to hear back from the memory controller. And that's why branch prediction is so important, and why it's such a large part of the design of modern processors.

Re:The "100 times greater"... (0)

Anonymous Coward | more than 6 years ago | (#22852346)

what??? There is no way they are getting close to c. Silicon isn't a superconductor. Hell, half the time it insulates! They might use tricks like pipelines and such to make it seem like a lot is being done really fast, but there is no way the signal propagation is reaching anything close to c. Especially when using clocks, where is slows everything to the clock's speed instead of just running as fast a possible.

Re:The "100 times greater"... (3, Funny)

FoolsGold (1139759) | more than 6 years ago | (#22851502)

Still, 100th the switching delay is not a bad target to be aiming at... 100Ghz processing!

I will physically reach out and strangle the first person to make a joke relating 100GHz to the system requirements of Windows...

Re:The "100 times greater"... (3, Funny)

mOdQuArK! (87332) | more than 6 years ago | (#22852354)

I'm so tempted by the idea of seeing a pair of disembodied hands lunging through my screen, but I'd better not risk it...

Re:The "100 times greater"... (2, Funny)

darkfire5252 (760516) | more than 6 years ago | (#22855446)

Besides, rendering the holotextures required to accurately represent the shape and movement of disembodied hands is no small task. In fact, it's so difficult that it will not be supported until Windows 17 (aka 'Fettershorn' [wikipedia.org] ) is released. Never mind the fact that the requirements for that edition are so steep that it'd requi... hold on a sec, someone's at the door...

Re:The "100 times greater"... (1)

danlock4 (1026420) | more than 6 years ago | (#22852978)

(also new to me ... a single-atom layer of carbon)
A single-atom layer of carbon is just that--one carbon atom. :-)

Re:The "100 times greater"... (1)

themacks (1197889) | more than 6 years ago | (#22853102)

Unfortunately the article doesn't mention a lot of other important characteristics of semiconductors. From what the article said, they basically have a new material for traces on PCBs, although at just one atom thick those would be easily damaged. For a semiconductor they have to be able to dope it. AFAIK carbon can be doped P but not N, so unless they can figure that out as well, it won't be any better than what we have now.

But... (1)

hax0r_this (1073148) | more than 6 years ago | (#22853814)

Will a 100Ghz processor play Crysis?

Unfortunate name (3, Funny)

Anonymous Coward | more than 6 years ago | (#22850876)

He must get "Herr Fuhrer" jokes all fricking day

Re:Unfortunate name (1)

Muhammar (659468) | more than 6 years ago | (#22850974)

Well he IS a gruppenfuhrer after all/

Re:Unfortunate name (3, Funny)

ScentCone (795499) | more than 6 years ago | (#22851296)

He must get "Herr Fuhrer" jokes all fricking day

Is it actually possible to Godwin a thread about microprocessor engineering?

Re:Unfortunate name (2, Informative)

cloakable (885764) | more than 6 years ago | (#22851556)

You just saw it!

Re:Unfortunate name (1)

X0563511 (793323) | more than 6 years ago | (#22851562)

YOU just Godwin'ed the thread.

"Herr Fuhrer" is just a title, literally translated as Mr. Leader.... just like we use Mr. President.

Re:Unfortunate name (1)

ScentCone (795499) | more than 6 years ago | (#22851820)

"Herr Fuhrer" is just a title, literally translated as Mr. Leader.... just like we use Mr. President

Well... um... who do you suppose that that title is actually most associated with? Hint: Germany's current president does not use that title, or any variation on it.

Re:Unfortunate name (2, Funny)

megaditto (982598) | more than 6 years ago | (#22852278)

Not in public, at least.

Re:Unfortunate name (2, Informative)

FuzzyDaddy (584528) | more than 6 years ago | (#22852454)

Germany's current president does not use that title
In part because she's a woman...

I, for one... (2, Funny)

ameline (771895) | more than 6 years ago | (#22850886)

I, for one, welcome our new carbon based overlords :-)

Seriously, however, I don't expect to see a CPU based on this anytime soon.

Re:I, for one... (1)

Gat0r30y (957941) | more than 6 years ago | (#22851026)

no worries, grab an eraser - problem solved!

Re:I, for one... (1)

The Ancients (626689) | more than 6 years ago | (#22851210)

Seriously, however, I don't expect to see a CPU based on this anytime soon.

so you shouldn't, at one atom thick.

Graphene, a single-atom-thick sheet of graphite...

Re:I, for one... (0)

Anonymous Coward | more than 6 years ago | (#22852306)

I, for one, welcome our new carbon based overlords
I, for one, heil mein new carbon based fuhrer.

Copper (0)

Anonymous Coward | more than 6 years ago | (#22850924)

Oh yeah well thats nothing compared to copper wire!

So.... (0)

WarJolt (990309) | more than 6 years ago | (#22850928)

Electricity conduction through graphene is about 100 times greater than that of silicon and could offer many improvements to things like computer chips and biochemical sensors.

So, when do I get my 360 GHz sixteen core processor?

Re:So.... (2, Funny)

ScrewMaster (602015) | more than 6 years ago | (#22850954)

So, when do I get my 360 GHz sixteen core processor?

The Sony Playstation 36, Holodeck Edition.

Re:So.... (2, Funny)

ZeroExistenZ (721849) | more than 6 years ago | (#22852170)

16-core processor?
You must be extremely conservative...

I'm waiting for my one MegaCore processor with 1,048,576 cores, while mocking the market-war with MegiCore processors who only have 1,000,000 cores, but perform better at rendering realistic 3D models of females.

Would oxidation be a problem? (4, Interesting)

MichaelCrawford (610140) | more than 6 years ago | (#22850932)

While you could coat it with a hard protective layer like aluminum oxide, I think it would be hard to protect it well enough to prevent oxidation from degrading a layer only one atom thick.

I recall that early compact discs had this problem, in which oxygen trapped in the plastic would oxidize the aluminum and reduce its reflectivity.

Big question (-1, Redundant)

clarkkent09 (1104833) | more than 6 years ago | (#22850936)

material of the future may be graphene rather than silicon

Yeah, but does this graphene feel like real breasts

Re:Big question (0)

Anonymous Coward | more than 6 years ago | (#22851030)

it might feel like a young bespectacled chap... it might feel like you! who knows?

Re:Big question (1, Funny)

the eric conspiracy (20178) | more than 6 years ago | (#22851128)

Yeah, like you know how real breasts feel.

Re:Big question (0)

Anonymous Coward | more than 6 years ago | (#22852018)

Just like sand bags.

Re:Big question (2, Informative)

the eric conspiracy (20178) | more than 6 years ago | (#22852442)

Chemistry 101:

Silica : crystalline silicon dioxide aka sand
Silicon : element # 14, greyish semimetallic crystalline
Silicone : Inorg. polymer typ. -Si(CH3)2-O- Liquid or can be rubber if crosslinked. Using for boob jobs.

Re:Big question (1)

fractoid (1076465) | more than 6 years ago | (#22854460)

Man, how old are you? 40? :P

What happened to using diamond? (0)

Anonymous Coward | more than 6 years ago | (#22850972)

I recall hearing some people making noise a few years ago about the possibility of using synthetic diamond as a replacement for silicon. What happened? Did the technology not work as predicted, or is graphene a superior material?

Re:What happened to using diamond? (1)

cyfer2000 (548592) | more than 6 years ago | (#22851950)

The band gap of diamond is big, it is good for high temperature purpose.

New material? (1)

CrazyColin (1261612) | more than 6 years ago | (#22850988)

I don't think graphene is a new material. It forms the basis of nanotubes, which have been studied for over a decade.

At heavy-load CPU temps? (1)

PhasmatisApparatus (1086395) | more than 6 years ago | (#22850998)

...In graphene the intrinsic limit to the mobility, a measure of how well a material conducts electricity, is higher than any other known material at room temperature. But how does it do at, say, 70C?

Dibs... (0)

Anonymous Coward | more than 6 years ago | (#22851014)

...on Graphene Valley

Bad for RF? (2, Informative)

WhoBeDaPlaya (984958) | more than 6 years ago | (#22851076)

One PITA in MMICs is the lossy substrate. More conductive = eddy currents = losses.

vfdsgfsd (-1, Offtopic)

voalse (1252046) | more than 6 years ago | (#22851092)

Re:vfdsgfsd (0, Offtopic)

WhoBeDaPlaya (984958) | more than 6 years ago | (#22851274)

Err... Bah Weep Granah Weep Ninni Bong?

Re:vfdsgfsd (1)

Arivia (783328) | more than 6 years ago | (#22852490)

If I had mod points, you would so get them all for that. Best reference ever.

Das Material fuhr das Future (0)

Anonymous Coward | more than 6 years ago | (#22851142)

Dis will be gut für das Kübelwagen MKIII! Ze Material is only one Atom zin!

Questions to ask proponents of new semiconductors (3, Insightful)

bperkins (12056) | more than 6 years ago | (#22851318)

1) Do you have a decent quality oxide for it?
2) Can you make good low resistance contacts?
3) Can it be doped?

Graphene probably fails 1 and 2 at this point. I'm not sure about 3.

2D (graphene) and 1D (carbon nanotube) semiconductor systems have a lot of trouble with surface effects ruining your ability to make decent devices.

Re:Questions to ask proponents of new semiconducto (0)

Anonymous Coward | more than 6 years ago | (#22851694)

4) Can it be etched easily to form structures?

Re:Questions to ask proponents of new semiconducto (2, Informative)

feranick (858651) | more than 6 years ago | (#22851816)

Yes, using conventional e-beam lithography.

Re:Questions to ask proponents of new semiconducto (1)

cyfer2000 (548592) | more than 6 years ago | (#22851884)

Yes, you can etch away all kinds of carbon with hydrogen plasma easily.

Re:Questions to ask proponents of new semiconducto (1)

Forbman (794277) | more than 6 years ago | (#22851890)

Yes. the linked article shows photomicrographs of quantum dots made on graphene surface that are set up via doping and can act as gates. I'm going to guess that perhaps a resistive base will be used, photolithographed, and via some magic process the graphene "wires" will be deposited onto the base into the channels or, perhaps pressed onto the ridges, before being doped further.

Re:Questions to ask proponents of new semiconducto (0)

Anonymous Coward | more than 6 years ago | (#22852630)

1. I suppose if they are using hafnium oxide, then an MBE system might be able to deposit a similar compound onto graphene.

2. Good question. If the answer to number #3 is that you can't dope, then you're probably screwed.

3. Doping might be possible as with SI using the III-IV elements.

4. What about the mobility of the holes? Or would this end up being a specialty player like GaAs in the high frequency range where the intrinsic electron mobility is pretty damn good (8500 cm^2/V-s) but the Hole mobility is down right terrible? (400 cm^2/V-s).

If the hole mobility is absolutely poor compared to the electron, it might never find a home in mass produced electronics like silicon is. But then again, if it's an order of magnitude better than that of Si, and can be economically and reliably produced then I imagine we'll see this first in mixers/modulators/clock gens/detectors/anything else that needs speed. Eventually it might trickle down to unseat the king of ICs, the almighty silicon.

Re:Questions to ask proponents of new semiconducto (1)

davros-too (987732) | more than 6 years ago | (#22852816)

5. Does it have 30 years of technology refinement behind it?

If electron mobility was important silicon would have been replaced by Galium Arsenide years if not decades ago. GaAs can pass all of the first 3 requirements suggested by the parent - but not in a scalable way. For example you can get a good quality insulator on it, but its just bloody hard to do.

Re:Questions to ask proponents of new semiconducto (1)

mathfeel (937008) | more than 6 years ago | (#22853290)

Because graphene has no gap, by simply gating and controlling the gate voltage you can induce charge carrier, which is essentially the same as dopping in a usual gapful semiconductor.

Graphene Valley? (1)

richtaur (1234738) | more than 6 years ago | (#22851446)

Silicon Valley has a way better ring to it.

Re:Graphene Valley? (1)

owlnation (858981) | more than 6 years ago | (#22851978)

Graphene Gulch is kinda cool though. It's much more Chuck Norris than Silicon Valley.

So Will Future Math Nerds (0)

Anonymous Coward | more than 6 years ago | (#22851458)

Take pride in what they can do with their graphene calculator?

hmm (0, Redundant)

kjayant (674123) | more than 6 years ago | (#22851476)

sorry.. no use unless it can be used for breast implants

Same old problems. (1)

Lewrker (749844) | more than 6 years ago | (#22851636)

Will I have to borrow a semi-conductor every class now ?
What if someone chews on mine ?

HFE (1)

kipman725 (1248126) | more than 6 years ago | (#22851638)

"how that thermal vibrations have an extraordinarily small effect on the electrons in graphene" does this mean that graphene transitors will have HFE as a stable paremeter?!? that would be seriously awsome!

Misread of Article Title (1)

HasselhoffThePaladin (1191269) | more than 6 years ago | (#22851718)

Did anyone else read the title as "Gangrene May be the New Silicon"?

Won't be used commercially for awhile (1)

vsage3 (718267) | more than 6 years ago | (#22851926)

Graphene wasn't even [b]fabricated[/b] for the first time until 2004 by the so-called "Manchester group". Carbon nanotubes were formally identified in 1991 and intentionally created shortly thereafter and we've done what exactly with them? As far as I know, companies like Nantero [nantero.com] , which uses carbon nanotubes as a basis for nonvolatile memory, are few and far between. I'm active in the field, and I can just say it's going to be a year or two until we even see transistor demos much less arrays of memory or logic circuits.

Graphene has some of the same problems as carbon nanotubes, so while doing basic electrical characterizations of this material are major news right now (that shows you how new this material is), ultimately using this material and convincing the 4 or 5 companies with the capital to have state-of-the-art fab facilities to switch over from silicon-based CMOS technology is looking way, way, WAY into the future.

What I'd like to build with this stuff is ... (1)

Skapare (16644) | more than 6 years ago | (#22851930)

... a Yagi antenna [wikipedia.org] resonant at a wavelength somewhere between 700nm and 400nm. Now I just need a high power transmitter and some feedline to connect to it.

But carbon is ee-vul!! We must reduce our graphene (1)

Iowan41 (1139959) | more than 6 years ago | (#22852032)

footprints.

Excellent, I can replace... (1)

LM741N (258038) | more than 6 years ago | (#22852406)

my Tin Foil hat with Graphean gray hair remover. (Graphite is grey to black right?)

Oh boy... (1)

Garridan (597129) | more than 6 years ago | (#22852486)

Chemists are going to be pissed to hear this! New periodic tables, new reactions, new names for all sorts of all sorts of chemicals. And where is the Silicon going to go? Also -- what are the geologists going to think? Over 25% of the earth's crust is made of the stuff!

Sieg Hail Michael S. Fuhrer! (0, Redundant)

Newton IV (666922) | more than 6 years ago | (#22852528)

Sieg Hail Michael S. Fuhrer!

let me clear up some confusion... (4, Informative)

Goldsmith (561202) | more than 6 years ago | (#22852712)

Graphene is certainly a lot like carbon nanotubes, but is much easier to work with. Where you have to hope to get a semiconducting crystal structure in a nanotube (or make crappy transistors based on defects), you can pattern graphene to make a transistor. Which directions you cut the 2D sheet determine whether it is metallic or semiconducting. There are some problems with this, and practically speaking any small channel (10 nm, I think) of graphene is semiconducting. Fuhrer has shown (along with other people) that graphene can make pretty good transistors (very fast switching, thermally stable and I'm sure I'm missing some stuff).

It can be doped. This is another thing Fuhrer has done (as well as other people... but this is his article we're talking about). You don't want to insert something into the crystal structure (that ruins it), but you can layer the top of it with potassium ions (about 1 per 1000 carbons), which dopes it just fine. This isn't a bulk semiconductor though, and the addition of charged impurities (dopants) decreases device performance (in bulk, it's a metal). You can very easily electrostatically gate graphene in any direction you want; transistors and PN junctions are easy to make this way.

It is not hard to make graphene. The "scotch tape" method from Manchester is widely used, but there are a number of other ways to do it which may be commercially viable: oxidizing graphite, ultrasounding graphite with special polymers (Dai's method), growing it from SiC wafers. Of course, none of these really work yet, and may never be economical.

Graphene is stable in air (almost all devices are measured in air at some point), and liquids. It's not going to spontaneously dissolve on you just because it's only 1 atomic layer thick. It's actually very robust.

It can be used with silicon processing techniques. People are using SiO2, HfO2 and all the usual silicon processing with it.

Big companies are looking at this material. IBM has already reported results on their work at physics conferences, I'm fairly sure that the more secretive companies (Intel) are also working with graphene... just like they worked with nanotubes.

Graphene for sale (1)

Muttley (53789) | more than 6 years ago | (#22855292)

A friend of mine works for Prof Andre Geim in the Mesoscopic Physics Group [man.ac.uk] at University Manchester and was one of the people to first prepare graphene crystals. They have a spin off that is selling graphene flakes to some interested industry altho the demand is not huge at the moment. If you want to play with graphene flakes of your own you can check them out here [grapheneindustries.com] .

It is interesting stuff - I saw Prof Geim speak about it and it seems to me one of these areas where quantum theory and experiment intersect, such as with Bose-Einstein Condensates. It's not really my field but the preparation of them is interesting. M

New? (1)

Thyamine (531612) | more than 6 years ago | (#22855574)

I didn't read the article (this is /. after all), but if it's made of graphite spread really thin (one atom thick), isn't it still just graphite? Just really thin? It sounds more like they discovered special properties in application of the material, as opposed to what it does when sitting in my pencil.
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