Jump to content

Scientists Get Atoms Ready for a Close-Up


mental invalid

Recommended Posts

Scientists Get Atoms Ready for a Close-Up

By KENNETH CHANG

 

 

Atoms are small, but not invisible.

 

Scientists at Lucent Technologies' Bell Labs have developed a microscopy technique that can zoom in on individual atoms within a chunk of silicon.

 

This is a big deal, in a minuscule way. Scientists previously were able to take pictures of individual atoms only when they were sticking out on the surface. Dr. David Muller, the Bell Labs physicist who led the research team, gave this analogy for the new work: If a typical eight-inch-long silicon wafer — the raw material that gets carved in computer chips — were scaled up to the size of the United States, then a single transistor would be size of a car, and an atom would be the size of a pinhead.

 

"We are able to locate the equivalent of a few pins, hidden in a few cars, somewhere in the United States," Dr. Muller said. The researchers reported their findings in the April 25 issue of Nature.

 

The ability to spot individual atoms becomes important as electrical engineers continue to jam more transistors into computer chips.

 

To tailor silicon's electronic properties, small amounts of other elements like antimony, which contribute electrons to conduct current, are diffused in. Because of the shrinking of transistors, it will become necessary in the coming years to check that the added atoms, or dopants, are going where the engineers think they are going. Otherwise, the transistor will not work because it will lack electrons.

 

"Now you can see where they are so it's not an issue," said Dr. John Silcox, a professor of applied and engineering physics at Cornell.

 

Put in too many antimony atoms, and the transistors also stop working. Images taken using the new technique help explain why.

 

The Lucent microscope shoots a narrow beam of high-energy electrons through a very thin sheet of silicon — about one one-thousandth as wide as a human hair — and looks at how the electrons are deflected. Antimony atoms are heavier than silicon and scatter the electrons at sharper angles, which gives away their positions.

 

Physicists believed they had a general idea why too many antimony atoms messed up the transistor, that antimony started clumping together and no longer donated its electrons. Scientists need to solve this problem because smaller transistors also require higher concentrations of electrons to work properly. But theorists argued about whether these clumps consisted of two or four antimony atoms.

 

In this case, a picture is worth a thousand equations. The answer is two.

Link to comment
Share on other sites

This forum is supported by the 12ozProphet Shop, so go buy a shirt and help support!
This forum is brought to you by the 12ozProphet Shop.
This forum is brought to you by the 12oz Shop.
Guest Are2

i figured this would come eventually

 

i am interested to see science begin to both refute and explain philosophical ideas in the coming decades..

 

getting closer to the root of ALL things...scary

Link to comment
Share on other sites

Guest imported_El Mamerro

I've seen pictures of atoms before... not individual atoms though, just clusters.

 

The pictures are really dissapointing. They're not acual "photographs"... since the process is not photon-based, what you actually see is a computer rendered image, a visual graph representing the numbers that result from the differing angles of deflection from the electrons. The result is not unlike inputting the dimensions of a building into a computer and having it render an image of it. So don't expect PHOTO photos, with depth and focus and stuff. Beer,

 

El Mamerro

Link to comment
Share on other sites

Originally posted by El Mamerro

I've seen pictures of atoms before... not individual atoms though, just clusters.

 

The pictures are really dissapointing. They're not acual "photographs"... since the process is not photon-based, what you actually see is a computer rendered image, a visual graph representing the numbers that result from the differing angles of deflection from the electrons. The result is not unlike inputting the dimensions of a building into a computer and having it render an image of it. So don't expect PHOTO photos, with depth and focus and stuff. Beer,

 

El Mamerro

 

yeah, kinda the same deal with hubble pictures, just a program somewhere interpreting data. i just learned about that last semester... really burst my bubble.

 

and those people at bell are definitely on the cutting edge of everything it seems.. wasn't it them a few months ago who made great breakthroughs in atomic/molecular computer processing? i'm pretty sure it was.

Link to comment
Share on other sites

Originally posted by test pattern

Aren't atoms smaller than a single wavelength of light?

 

Yes, they are.

 

 

So how can we see them?

 

I don't think atoms are smaller than quanta of light, because we can find their exact location and velocity at one time...(I think?)

You're thinking of subatomic particles (or maybe just electrons and smaller), which we can't really "see" because observing them requires interacting with them and changing their locations/velocities, which is why scientists represent them as probability clouds.

It's also interesting to me that you referred to light as a wavelength. Correct me if I'm wrong here, but Light has been observed to have both wave and particle like properties, which many believe is caused by interactions between different universes in a multiverse of which we are part.

 

Quandom Phone makes me roam?

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...