IBM reports it has invented a more efficient way to recycle scrap silicon wafers from semiconductor firms for the solar industry:
The technique basically involves polishing a scrap wafer with water, an abrasive pad, and a piece of machinery ordinarily used to smooth out the pits and valleys in production chips. Rather than smooth out the surface of the wafer, the primary goal of the water polishing process is to erase any intellectual property or chip designs on the wafer.
"We use it literally to scrap off the integrated circuits," said Tom Jagielski, an engineering manager at IBM working on the project.
Water makes the process more eco-friendly--usually, wafers get dipped in abrasive chemicals or blasted with tiny glass beads to remove circuitry.
IBM estimates that around 3 million wafers get scrapped a year. If you could turn those all into solar panels, the panels would be capable of generating 13.5 megawatts of power.
That would represent a small percentage of the world's solar output. Sharp, the largest solar panel maker in the world, can manufacture more than 600 megawatts of solar cells a year. But a global silicon shortage--which started after large subsidies in Germany goosed solar demand in early 2004--makes any source of processed silicon welcome.