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Silicene Discovered: Single-layer Silicon That Could Beat Graphene To Market
MrSeb writes "Numerous research groups around the world are reporting that they have created silicene, a one-atom-thick hexagonal mesh of silicon atoms — the silicon equivalent of graphene. You will have heard a lot about graphene, especially with regard to its truly wondrous electrical properties, but it has one rather major problem: It doesn't have a bandgap, which makes it very hard to integrate into existing semiconductor processes. Silicene, on the other hand, is theorized to have excellent electrical properties, while still being compatible with silicon-based electronics (abstract). For now, silicene has only been observed (with a scanning tunneling electron microscope), but the next step is to grow a silicene film on an insulating substrate so that its properties can be properly investigated."
None of those have the same crystal structure as carbon or silicon, which both form diamond lattices due to being group IV materials. As someone who works with silicon/gallium arsenide semiconductors and crystal formation, I think this is pretty exciting news. There's a large difference between observing something and making it work the way you want it to, though, so my guess is it'll be a while before silicene can be properly studied, let alone used in commercial semiconductor devices.
Plasticene?
I'm still waiting on the atom-thick holographic film, Holocene(tm).
You can hold down the "B" button for continuous firing.
Valence 4. I would assume Germainiumicene will be the next with a band gap of .67
So, Silicene has just been observed for the first time under a scanning tunnel microscope, has had its properties only theoretically proposed, and is hoped to be "as miraculous as Graphene". Nevertheless, the author of the article already believes that it will beat Graphene to the market? Sheesh! Are all headlines nowadays conjured up by a dedicated company full of marketing types?
"silicon — a material which will probably reach its physical limits in the next 5-10 years" Haven't they been saying that since 1980?
Thought this might help your predictions Notice where Carbon and Silicone are.
And the flexible version.... Pliocene
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
I would be a little concerned that the silicon mono-layer would grow a natural oxide very fast and thus consume the silicon?
The solution in a HEMT transistor is cool in this respect. It is using an un-doped IV-V semiconductor next to a highly doped layer and excess carriers will form a two-dimensional electron gas at the interface. The carriers will move along the surface of the un-doped semi-conducter that since it is un-doped have better mobility and fewer defects than doped material. It must be something along this property they try to re-create with a silicon mono-layer.
I think you are confused
Learn to chemistry. It's the 4 valence behavior that both provides the familiar diamond geometry as well as allowing hex-rings with extremely low electron latency.
The part I'm more curious about is whether this kind of behavior can be applied to heavier elements that do not hold as tightly to their electrons. I doubt it, because I'm sure someone would've already noticed if tin or lead was an exceptionally good conductor. Still, few people expected carbon to be as capable a conductor as it is with certain geometry, so I will not completely dismiss the idea of careful lead sculptures being a favored circuitry.
I'm waiting for the censored version of the Oxygen-Boron layer: OBscene.
I apologize, I was hurried and didn't explain myself very well in the first post. You're correct, graphene (and apparently now silicene) has sp2 hybridization, but as the AC reply to your post suggests, it's the fact that carbon is group IV that gives it such interesting characteristics as a 2D structure. As a sidenote, I'd hesitate to assume silicene's electronic properties - silicon doesn't naturally form anything like graphite (i.e. stacks of loosely bonded monolayers) that I know of and since the properties of diamond and graphene are so different and I don't study monolayer materials, it'd be irresponsible of me to say "silicene will have X band gap" etc. Very interesting stuff, though, I'll be interested to see how this develops.
"Because of its unique physical properties, graphene, a 2D honeycomb arrangement of carbon atoms, has attracted tremendous attention. Silicene, the graphene equivalent for silicon, could follow this trend, opening new perspectives for applications, especially due to its compatibility with Si-based electronics. Silicene has been theoretically predicted as a buckled honeycomb arrangement of Si atoms and having an electronic dispersion resembling that of relativistic Dirac fermions. Here we provide compelling evidence, from both structural and electronic properties, for the synthesis of epitaxial silicene sheets on a silver (111) substrate, through the combination of scanning tunneling microscopy and angular-resolved photoemission spectroscopy in conjunction with calculations based on density functional theory."
This is from Phys Rev Letters (DOI: 10.1103/PhysRevLett.108.155501
they show reasonably convincing LEED (low energy electron diffraction) and STM (scanning tunneling microscope) images of the putative hexagonal close packed array of Si atoms.
It makes me wonder if anything will ever replace silicon.
Good question. One of the great things about silicon from a device manufacturing perspective is that it forms an insulating oxide. Don't know if silicene will do that without compromising its desirable electronic properties. Maybe some of the modelers among us can tell what will happen to the electron structure when we start plugging oxygen atoms onto silicene?
Erm - it's *you* who should learn chemistry. If you believe that sp2 hybridized graphite (excellent conductor, very soft) and sp3 hybridized diamond (insulator, very hard) have similar properties just because it's the same group IV element, then - well... - sorry to say... - but you are full of shit.
And your senseless mumbo-jumbo on conductivity sadly just proves it.
It'll likely be manufactured under heavy vacuum, then sealed, and never exposed to any O2.
But no one has asked the really important question. How do you pronounce silicene?
make imaginary.friends COUNT=100 VISIBLE=false
Toil onwards, nerds. I'll be hangin down at Starbucks with me iPhone, iPad, and Macbook Air as part of the self-referential Hipsterscene
You will have heard a lot about graphene, especially with regard to its truly wondrous electrical properties
In most press releases about graphene I read lately, the focus was on its mechanical properties, and the fact that it is conductive would be merely an (often convenient) side effect.
He wins, that's about as mono-layer as you can get!
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
You are probably alluding to discovery that bi-layer or tri-layer graphene stacks can be induced to have a tunable bandgap... http://www.lbl.gov/msd/assets/docs/highlights/09-9FengWang_bilayer_graphene.pdf
The fact that C and Si lie in the same group allows for the special bonding (think valence electrons and preferred oxidation states) that they have although Si might have the band gap that is needed that C doesn't. tocsy was referring to this. You don't see varied structures in Li or Na or K since they aren't like Carbon or Silicon.
I thought mono was part of the MS ecosystem?
Mononucleiosis, maybe!
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
I'd guess 'silly seen'
No colour or religion ever stopped the bullet from a gun
he didn't say that graphene includes sp3 hybridized C atoms as in diamond. he said that both carbon and silicon form diamond lattices, which makes Si more similar to C than other elements like lithium, sodium etc. this is true. Si forms diamond cubic crystals.
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Is this the MPAA? Is this the RIAA? Is this the DMCA? I thought it was the USA!
Note, however, that the insulator commonly used in silicon systems is silicon dioxide, formed by the in place oxidation of silicon. Forming an enduring insulator on a silicene layer is going to be tricky. Come to think of it, I bet forming an insulator on a graphene layer is also difficult.
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