REPTILE · Repairing of Photovoltaic Wafers and Solar Cells by Laser Enabled Silicon Processing

REPTILE will develop a laser-based technique for repairing of broken and defective silicon cells and wafers, improving the yield of the European wafer and cell manufacturers, and representing an opportunity for European SMEs for the reuse of scrapped and recovered silicon to produce custom PV products at low price, covering a growing demand for small format, semi-transparent or custom shape PV cells.The concept is based in the automated defect recognition and classification performed on C or D class cells, and the subsequent laser reprocessing to obtain a smaller A-class cell.Research efforts will be focused in image-based cell inspection, computer-based detection of optimal process path, precision laser cutting, laser ablative isolation, and automatic handling of the processed parts. Advances will be made in defect classification and interpretation algorithms by luminescence and thermal imaging. In the field of laser processing, advantage will be taken from high brilliance laser sources and advanced scanner control for performing surface processing in novel repairing techniques. These developments will allow the integration of the whole process in a single station which comprises automatic wafer/cell handling, recognition, processing and classification.The work plan is designed to end up with a prototype system, able to automatically select and cut or isolate non-defective areas in scrap cells and wafers, with computer based calculation of the best geometry for maximum efficiency and minimum waste of material. Proof-of-concept modules will be then built, installed and tested to asses the market potential.The project will bridge the gap between the need of the PV market for a solution for their rejected cells and wafers, and the capacity of European SMEs to reprocess this material and take economical advantage from its recovery. Hence, this project can lead to market replication and easily be implemented in a profitable way, opening new markets for SMEs.""