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Solar Cells Crystallized Out of Molten Silicon
Hot Toddy sends in a link to a story up on Digital World Tokyo about a more efficient process for manufacturing solar cells. It involves dropping molten silicon from a height of 14 m; surface tension causes tiny spheres 1 mm in diameter to form; the silicon crystallizes in the 1.5 seconds of free-fall. The spheres can be mounted on surfaces of any shape. They capture light from many directions, increasing their solar efficiency. Kyosemi is the company behind the Sphelar technology. Some of the pages on this site date to 2003 and the status of most listed Sphelar products is either "under development" or "engineering sample is available."
Neat! This is the same method that was used to make cannonballs during the US Civil War.
I can't find any references to cannon ball manufacture on Wikipedia, but my high school had a cannon forming tower (it was originally a civil war arsenal).
Outside of that, the more techniques the merrier! I'm somewhat curious how they create a PN junction out of a homogenous liquid of silicon, but I suppose that can be done afterwards. I'd also be a bit curious if it's single crystalline. I very much doubt it, as there is no seed crystal to nucleate on, so there should be a lot of independent surface nucleation sites (IAAMS).
I wonder if we could use the silicon from all the computers in our landfills to make solar cells?
Hot liquid metal inside an aircraft - what fun! Look up "liquid metal embrittlement" to see why this would have to be done very carefully and why you currently cannot take mercury on an aircraft. In short the liquid metal gets into any small flaws, dissolves it into a sharp crack quickly, and then after a short time the crack gets long enough that it goes at the speed of sound in the material - more than 4miles/second (6.6km/s) in steel.
The same process with molten glass produces the tiny beads for Scotchlite(TM) reflective material, which has been around for half a century or so.
Nice idea, I'd also check out concentrating solar power though. To me this seems to be a simple, conventional engineering task. Future information here: CSP on The Oil Drum