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In fact, the devices that de Heer announced in December were carved into graphene using techniques very much like those used to manufacture silicon chips today. "That's why industry people are looking at what we're doing," he says. "We can pattern graphene using basically the same methods we pattern silicon with. It doesn't look like a science project. It looks like technology to them."
Graphene hasn't always looked like a promising electronic material. For one thing, it doesn't naturally exhibit the type of switching behavior required for computing. Semiconductors such as silicon can conduct electrons in one state, but they can also be switched to a state of very low conductivity, where they're essentially turned off. By contrast, graphene's conductivity can be changed slightly, but it can't be turned off. That's okay in certain applications, such as high-frequency transistors for imaging and communications. But such transistors would be too inefficient for use in computer processors.
In 2001, however, de Heer used a computer model to show that if graphene could be fashioned into very narrow ribbons, it would begin to behave like a semiconductor. (Other researchers, he learned later, had already made similar observations.) In practice, de Heer has not yet been able to fabricate graphene ribbons narrow enough to behave as predicted. But two other methods have been shown to have similar promise: chemically modifying graphene and putting a layer of graphene on top of certain other substrates. In his presentation in Washington, de Heer described how modifying graphene ribbons with oxygen can induce semiconducting behavior. Combining these different techniques, he believes, could produce the switching behavior needed for transistors in computer processors.
Meanwhile, the promise of graphene electronics has caught the semiconductor industry's attention. Hewlett-Packard, IBM, and Intel (which has funded de Heer's work) have all started to investigate the use of graphene in future products.
Making graphene with clean edges will be key to using it for high-speed electronics.
IBM shows that graphene transistors could one day replace silicon.
The atom-thick carbon material could have optoelectronic applications.
Graphene cann't take punishment.
Graphene is old, very old. Used as bearing material saturated in paper or leather in horse drawn carts & carriage axles.Graphene was never made for constant billions of on/off voltage variations in complex non harmonic enviorment. It is low friction due to its shape, it is electrical due to properties of that element, yet it varies widely from one molecule & situation to next. Machine run on graphene will stumble & crash, over & over with normal useage. Todays cpu uses metals that are tightly bound, graphene is lossely structure. PING of graphene is NOT precisely repeatable.Graphene will just stop or simply misfire often.
Signed:PHYSICIAN THOMAS STEWART VON DRASHEK M.D.
Re: Graphene cann't take punishment.
You are correct, except that you are talking about graphite, not graphene. Graphite is made of many layers of graphene, which are very loosely bound to one another. The graphene layers readily come apart and slide across each other, making graphite perfect for the uses you cited. In contrast, the INTRA-layer bonds -- the bonds WITHIN graphene -- are very strong.
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Manufacturing in the United States is in trouble. That's bad news not just for the country's economy but for the future of innovation.
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jacklewisr
4 Comments
Imaging at one nanometer
One of the interesting traits of graphene is that it can support building transistors at approximately a one nanometer scale. To build at this scale, however, will require an advanced imaging technology if current manufacturing methods are to be used. Recent developments in plasmonics to focus electromagnetic energy at this scale may be a possible solution.
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