By Kevin Nguyen, SEMI International Standards

The increasing number of players in the market for PV silicon feedstock materials has introduced a wide variety of material grades. This wide variety requires considerable efforts from both suppliers and end users to achieve a common understanding of the material specifications, as well as the impacts of the different materials on the quality and performance of the resulting PV product.

The SEMI Standards PV Silicon Materials Task Force was established in 2009 to develop a standardized specification for solar grade feedstock materials, which will allow manufacturers to produce consistent silicon solar cells. When this specification is approved, polysilicon and cell manufacturers will be able to use the standard to specify chemical (donor concentration), dimensional (chunk, rod, bricks), and packaging characteristics on their purchase order for feedstock materials. The purchase order form will also include test methods to validate specified characteristics.

After receiving input from major polysilicon suppliers, the Task Force has recently issued a ballot that is now available for voting. Document 4805A, Specification For Virgin Silicon Feedstock Materials For PV Applications may be accessed with other Cycle 5-2010 PV ballots at http://dom.semi.org/web/wstandards.nsf/NTB. The voting deadline is September 8, 2010. Official committee adjudication of the ballot will take place at the next European SEMI Standards PV Committee meeting, which will be held on October 19, 2010, at Solarwatt in Dresden, Germany. A complete schedule of related meetings can be found at: http://www.semi.org/en/Standards/ctr_038163 .

For more information on this ballot and other PV Standards development efforts underway at SEMI, please visit www.pvgroup.org/standards, or contact your local SEMI Standards staff.

SEMI PV Group - The Grid, August 2010