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One-Atom-Thick Silicene Transistors May Lead To Dramatically Faster Chips
Zothecula writes: As recently as 2010, human-made silicene – an atom-thin form of silicon – was purely theoretical. But now the exotic material has been used to make transistors, and researchers have found that silicene's electrical properties lend it extraordinary potential in powering the next generation of computer chips. The new method (abstract) of creating the silicene reduces its exposure to air. "To start, the researchers let a hot vapor of silicon atoms condense onto a crystalline block of silver in a vacuum chamber. They then formed a silicene sheet on a thin layer of silver and added a nanometer-thick layer of alumina on top. Because of these protective layers, the team could safely peel it of its base and transfer it silver-side-up to an oxidized-silicon substrate. They were then able to gently scrape some of the silver to leave behind two islands of metal as electrodes, with a strip of silicene between them."
I'm curious, which one gets fabbed first?
Silicene has a tunable band gap. That makes it more useful for transistors. But, unlike graphene, it will spontaneously oxidize. So there are some big problems to iron out with both graphene and silicene. This research is mainly about dealing with the oxidation problem. If we can solve that, then silicene will likely "win" the race to fabrication.
The problem is graphene has no band-gap, so it's pretty useless as a transistor (unless it's heavily doped I suppose). That's not to say it can't be doped, or that there aren't any uses for graphene other than transistors.
Graphene has the unfortunate property that transistors using it don't actually have an "off" mode - Just a "low" and "high". So although it might give us crazy-fast switching times, it will leak current worse than an XFinity modem. But hey, we all miss the good ol' days of using our P4 gaming rigs as space heaters, right?
Silicene, by comparison, does have a tunable band-gap, meaning that it should get around that limitation of graphene.