To enhance higher yield and also to produce high-efficiency solar cells, Applied Materials has made available a new solar wafer inspection system, which does 100 percent in-line wafer inspection and automatically predict wafer cell efficiency through photoluminescence (PL) technology.
“The Vericell system enables real time yield optimization,” said Jim Mullin, vice president and general manager of Solar Products for Applied Materials’ Energy and Environmental Solutions Group. “Our customers can now cost-effectively track incoming and outgoing wafer quality and adjust manufacturing processes to improve yield and binning. As the PV industry keeps pace with the “efficiency clock” and transitions to more advanced cells, controlling manufacturing yield becomes a high value problem. The Vericell system has proven its value in predicting yield and increasing profitability in manufacturing at several customer sites.”
The PL technology uses multiple sensing and advanced algorithms to predict solar cell efficiency from bare wafer material with a me now range prediction error of less than 0.15% on multi-crystalline silicon wafers.
By using this system solar PV manufacturers can identify and remove low-efficiency wafers and also identify those that require process modifications.
This new test system automatically evaluate each wafer to find and eliminate defective wafers from production. It measures and reports on a range of parameters including wafer thickness, thickness variations, warp and resistivity. The system also detects defects including saw marks, chipped edges, stains, and micro-cracks.
The Vericell system is available with Applied’s proprietary yield management software that can be utilized to collect, consolidate and analyze real-time data. This software allows customers to quickly identify and act on yield-impacting events to optimize their entire manufacturing line.