Wacker Builds German Facility for Granular Solar Polysilicon

The new production facility, with an annual nominal capacity of 650 metric tons, will manufacture granular solar-grade polysilicon from trichlorosilane using the fluidized-bed technology.

Granular polysilicon offers processing advantages to solar-wafer manufacturers that use certain production techniques. Wacker successfully tested its new method in pilot reactors over the past 36 months and is now initiating first-ever commercial-scale production.

"Tests by customers who manufacture solar wafers (the starting material for solar cells) via continuous crystallization show that processing granular polysilicon is far more efficient than conventional techniques using polysilicon chunks," said Ewald Schindlbeck, president of Wacker Polysilicon.

"Moreover, the comparatively low energy consumption vis-à-vis conventional deposition positively impacts the energy balance of solar cells," he added. "Another advantage of our new method lies in the high yield provided by trichlorosilane as a feedstock."

For more than 50 years, Wacker's Burghausen site has been producing hyperpure polycrystalline silicon for the semiconductor industry.