Surface treatment of high performance multicrystalline silicon wafers
MetadataShow full item record
This master thesis investigates the properties of high performance multicrystalline silicon, and the production line of black multicrystalline siliconsolar cells with PERC architecture. Possible solutions to achieve higherefficiency were explored, and different steps in the production route wereexamined. Three steps of the production chain were in focus. Decreasing the polishingtime by 70 seconds proved to enhance efficiency. Optimizing the emitterdoping process by varying parameters in the deposition step, achieved amore uniform doping distribution across the wafers, and improved overalldoping homogeneity by reducing standard deviation by 24%. Further, the rear passivation step was investigated, and it was found thatby increasing the thickness of the Al2O3-layer from 14 to 24 nm, efficiencywas improved. The final experiments combined the best result in each of theother steps, and optimized parameters were implemented in the productionchain for an overall optimization. A champion efficiency above 20% wasachieved, which is 0.23% higher than average baseline efficiency for allPERC wafers investigated in this thesis.