IBM Silicon Wafer Reclamation Process Saves Energy, Provides Solar Industry with New Supply

IBM (NYSE: IBM) announced that it has developed and is using an innovative new semiconductor wafer reclamation process at its Burlington, VT manufacturing facility and intends to provide details of the new process to the broader semiconductor manufacturing industry.  The new process uses a specialized pattern removal technique to repurpose scrap semiconductor wafers to a form used to manufacture silicon-based solar panels.

Semiconductor manufacturers are very concerned that intelluctual property on defective wafers might be recovered if they are sold. To avoid this they have been using much more expensive sandblasting, or chopping them up and disposing of them in landfills. IBM's process wipes away any traces of the original chip design, which could ease those worries.

Through this new reclamation process IBM is now able to more efficiently remove the intellectual property from the wafer surface, making these wafers available either for reuse in internal manufacturing calibration as "monitor wafers" or for sale to the solar cell industry, which must meet a growing demand for silicon material to produce photovoltaic cells for solar panels.

According to Cleantech, IBM's machines use an abrasive pad and deionized water to polish the patterns off of scrap wafers, which are thin discs of silicon material used to imprint patterns that make finished chips for electronics.

"One of the challenges facing the solar industry is a severe shortage of silicon, which threatens to stall its rapid growth,” said Charles Bai, chief financial officer of ReneSola, one of China's fastest growing solar energy companies. "This is why we have turned to reclaimed silicon materials sourced primarily from the semiconductor industry to supply the raw material our company needs to manufacture solar panels."

The new wafer reclamation process produces monitor wafers from scrap product wafers - generating an overall energy savings of up to 90% because repurposing scrap means that IBM no longer has to procure the usual volume of net new wafers to meet manufacturing needs. When monitors wafers reach end of life they are sold to the solar industry.   Depending on how a specific solar cell manufacturer chooses to process a batch of reclaimed wafers - they could save between 30 - 90% of the energy that they would have needed if they'd used a new silicon material source.

IBM estimates that up to 3.3% of wafers, that are started, are scrapped. In the course of the year, this amounts to approximately three million discarded wafers.

The process is currently in use at the Burlington, VT facility and in the process of being implemented at IBM's East Fishkill, NY, semiconductor fabrication plant.  For the IBM Burlington site, the annual savings in 2006 were more than half-a-million dollars.   The projected ongoing annual savings for 2007 is nearly $1.5 million.

Comments

[Chanranshu Pandya]

"Recycling" may bring down the costs and may improve the avaiability to many more people in developing countries.

[bigTom]

Realistically, this will only increase the amount of available solar silicon by a percent or two. It is nice that the utilization of industrial scrap is improved, but this project will only have a pretty small impact on the solar industry overall.

[GreyFlcn]

Thats why solar processes that don't use silicon can be better.

For instance CuInGaSe, or TitaniumOxide

[GreenPlease]

Every bit helps!