Wafer-Thin Silicon Discs on Leading Edge of German R&D
The German Fraunhofer Institute continues to make progress in reducing the cost of wafer used to produce solar cells.
Roughly a third of the costs for a silicon solar module is accrued before production of the wafer even starts… Holding a wafer-thin silicon disc between his two index fingers, Schönfelder explained that it is the industry standard, roughly 180 micrometres thin. He said that his research project is about producing even thinner silicon wafers, as well as reducing the breakage rate… Fraunhofer’s DiaCell project… DiaCell refers to the name of the diamond wire saw involved in the research… Reducing costs for the entire value chain is the mission of the DiaCell research project… This sawing gap created by the wire cutting process is incredibly expensive, representing a nearly 50% material loss… another research effort is developing wafer-splitting strategies to produce zero material loss. Instead of sawing the wafer into slices, with wafer splitting, a special polymer is glued to both sides of the wafer. When in a frozen state, the special polymer layer contracts, developing a strong enough force to split the wafer into slices.