IBM Chips In a Wafer
by Tim McGee, Helena, MT, USA on 11. 2.07
Although silicon is one of the most abundant elements on earth, single crystal silicon wafers don't grow on trees- yet. It is actually quite an extensive and expensive process to produce silicon wafers, which are used to create everything from computer chips to solar cells. As announced via the IBM video above, IBM'ers in Vermont have devised a process that allows their rejected wafers to be repurposed for solar cells.
From what I can glean, the process involves water and gentle scrubbing to remove the microstructures on the surface of the wafer. The removal of these features is key to recycling the wafer, as the bits scrubbed off represent important intellectual property (IP) for the company. By removing the sensitive information, the wafer can be saved from being crushed into dust, and used by other companies.
IBM has said it will license the technology to other manufactures, and could result in around 3 million wafers repurposed per year. A nice bonus for the solar cell companies that use these silicon wafers as a core to their technology. Also a nice bonus for IBM, who has a waiting customer for what would normally be a waste product.
Feeding on the waste stream of the computer chip manufacturers has nursed the solar industry along for several decades. I'm glad IBM is helping to enrich the milk a bit, and the IBM'ers in Vermont certainly deserve a hand for their ingenuity. Pragmatic steps like this can slowly and effectively change our system towards sustainable goals.
However, I can't help but wonder where the silicon microstructure sludge produced in the process ends up, and haven't found anything regarding the waste stream process itself. Any IBM insiders out there should feel free to enlighten us on this point.
I would also like to see the solar industry find its own feet without the need for single crystal silicon, and move to a more sustainable feedstock. After all, how often does IBM make this kind of a mistake? (Answer: 3.3% in this case)
if it's pure silicon sludge, shouldn't it not pose a problem if it's reintegrated into the soil?
I was fortunate enough to get a guided tour of the Vermont facility several years ago. I was impressed that they are keen on "using things that work." For instance, though the whole place was the most technologically advanced building I'd ever been inside and they had fancy custom devices everywhere, there was one critical testing machine run by a Commodore 64. Apparently it had been sitting there for years and years just doing its thing. (If I remember correctly it was actually the device that tests for manufactured chip faults--so maybe it's part of the process mentioned in the post.)
Perhaps something about the corporate culture at IBM encourages this type of thinking?
It's great news that IBM is sharing this technology across the industry. Thanks to IBM and this technology Solar Power is going to become much more cost effective very quickly.
Currently there are several silicon factories onder construction, the first will com online in 2008.
This feels like a good case of "if you've got lemons, make lemonade" to me.
hee hee Commodore 64. my sibs and i each had one in the early 80's. my little sister was 1 at the time. lol. dad was/is obsessed with computers.
that's awesome that they are still using one. if it ain't broke, don't replace it.
Harold:
Recycled silicon wafers are not just inert silicon. They are impregnated with all kinds of nasty metals that people have never even heard of. I applaud IBM for putting these products back into the production stream, rather than letting them corrode in a landfill and fill our soils with the most diabolical leachate imaginable.
I agree Rob, but the leachate in this case is (in part at least) being washed off prior to recycling. The question is where's it going to and how's it being processed to decrease the diabolical aspects.
I am hoping someone in the know will post the answer. Until then, it seems this is a nice story about a company trying to do the right thing. How nice and how right depends upon the whole story.
Maybe one day they'll put complete computers on the back of our solar panels in a 2 for 1 deal.