SiliconPV 2011 1/3 LOSS ANALYSIS AND IMPROVEMENTS OF INDUSTRIALLY FABRICATED CZ-SI SOLAR CELLS BY MEANS OF PROCESS AND DEVICE SIMULATIONS

We model Cz cells, fabricated in a pilot line, with a combination of process, device and circuit simulations. This allows us to separate the various resistive losses and to determine the recombination losses contributed from various device components. Such data are vital for identifying performance improvement strategies. As the model is based on currently fabricated cells, it gives precise predictions for specific cell improvements and the associated thermal budgets. We forecast the extent to which the emitter needs to be improved until the recombination losses in the boron-doped Cz base dominate. At that point, the cell reaches an efficiency of 18.9% after degradation. To increase the efficiency beyond about 19.4% after degradation, the boron-doped Cz material needs to be improved.