October 31, 2007 – IBM says it has developed a method to repurpose scrap semiconductor wafers that’s more efficient at pattern removal, to be reused as monitor wafers or sold to solar firms and converted into solar panels. The process is currently in use at IBM’s Burlington, VT, facility, and is being implemented at its semiconductor fab in East Fishkill, NY.
Getting monitor wafers from the reused scrap generates up to 90% energy savings, since IBM doesn’t have to procure net new wafers. When the monitor wafers reach end-of-life they are sold to the solar industry, where (depending on individual solar cell firms’ processes) hey could save 30%-90% energy vs. new silicon material sources.
The process saved about $500k at the Burlington site thanks to reduced spending on monitor wafers and better efficiency in IBM’s wafer reclaim program. Projected annual savings are nearly $1.5M in 2007, plus a one-time savings of >$1.5M for reclaiming stockpiled wafers.
About 3.3% of the world’s 250,000 wafer starts/day end up scrapped, adding up to ~3 million discarded wafers annually, according to SIA data cited by IBM. That amount could otherwise generate 13.5MW of solar energy, produce 57M kWh in solar panels (12-hour day x 365 days), and power 6000 homes (9500 kWh/year/house), IBM notes.
The new process recently won an award from the National Pollution Prevention Roundtable, for “most valuable pollution prevention.”