Melting Microchip Defects May Extend Moore's Law

schliz lets us know about research out of Princeton on melting away defects on microchips using a laser. The new technique, termed Self-Perfection by Liquefaction (SPEL), was published in the May 4 issue of Nature Nanotechnology. Researchers have traditionally approached chip defects by trying to improve the microchip fabrication process, but this eventually reaches fundamental physical limits to do with random behavior of electrons and photons. By focussing on fixing defects, the new method enables more precise shaping of microchip components, and engineers expect to dramatically improve chip quality without increasing fabrication cost. The before-and-after images are remarkable. Here's a diagram of how the process works.

read the article

[emj]

here is a larger version [princeton.edu]

Corrected picture link

[bopo_the_mofo]

here... http://www.princeton.edu/pr/pictures/a-f/chou/Chou_micrographs.jpg [princeton.edu]

Better Before and After

[Garganus]

better link: http://www.princeton.edu/pr/pictures/a-f/chou/ [princeton.edu]

Re:Annealing?

[bhima]

As I understand annealing it removes internal stresses created by uneven heating and cooling. This process smoothes etching or deposition defects.

quick explanation

[anmida]

I'm a materials scientist, so hopefully I can explain this quickly for you all :)

The images that are given (before and after) are some scanning electron microscope images. Think optical microscope except with electrons. Anyway, there is a serious improvement in the structure - the edges are a lot cleaner and more defined. This is a really simple and beautiful way of letting Nature do the hard work for us. What this is doing is liquifing the material and letting surface tension pull it into the lowest-energy configuration (least amount of surface area locally).

It's really a neat way of doing it, because fabrication is really tough - uses either chemical etching or some method of particle bombardment to remove atoms. There's a big trend in matsci to build down, and build up, at the same time at the nanoscale. Think of this as the "error-correction" process after fabrication.

--This is not the same as annealing - annealing is a solid-state process, putting energy into the material to enable atoms to move and remove stress and other small defects from the material.

Hope that helps :)

Re:Misleading title?

[teslar]

I doubt it could fix a "real" defect

Irregular shapes are a "real" defect. From the first paragraph of TFA:

even tiny defects in the lines, dots and other shapes etched on them become major barriers to performance

Re:Before and after image resolution.

[Anonymous Coward]

It WAS the thumbnail -- all better now. Princeton's Web team swapped the file to make the link work.

They did it with semiconductor, thats why its cool

[GanjaManja]

quote from article:

Simple melting by direct heating has previously been shown to smooth out the defects in plastic structures.
This process can't be applied to a microchip for two reasons. First, the key structures on a chip are not made of plastic, which melts at temperatures close to the boiling point of water, but from semiconductors and metals, which have much higher melting points.
Heating the chip to such temperatures would melt not just the structures, but nearly everything else on the chip. Second, the melting process would widen the structures and round off their top and side surfaces, all of which would be detrimental to the chip.

Chou's team overcame the first obstacle by using a [...] laser [...] because it heats only a very thin surface layer of a material and causes no damage to the structures underneath. The researchers carefully designed the pulse so that it would melt only semiconductor and metal structures, and not damage other parts of the chip. The structures need to be melted for only a fraction of a millionth of a second, because molten metal and semiconductors can flow as easily as water and have high surface tension, which allows them to change shapes very quickly.

That's pretty amazing, that the semiconductor and metal self-correct via surface tension, and by using a directed laser pulse so you only affect specific areas of the chip.

Re:Having worked in manufacturing...

[J.R. Random]

This isn't a matter of detecting defects and fixing them. It is a matter of applying a finishing step that improves the whole chip at once. You can be sure than chip manufacturers try very, very hard to get things right the first time. But if you read the article you would know that there are basic physical processes that make a certain amount of randomness and jagginess inevitable, which the laser process fixes.

Here's what annealing does in glass.

[ahfoo]

One of my dozens of hobbyist hats is my glassworkers hat and annealing is a big deal in glasswork. From my experience with glass, I would say that annealing is probably the wrong term because this involves an actual deformation. Typically in annealing you want to stay below the point at which deformation occurs and your main concern is to create a gradual change in the temperature over time in order to eliminate internal stresses. So that's probably not the best word to use in this case since this is not about alleviating internal stresses but actual changes in the shape of the product.
     

Re:Er um, maybe not so much

[Anonymous Coward]

Jesus, could you try to sound less smug when making an insightful comment. You raise a good point, but "How convenient" just makes you sound like a prick.