Influence of defects and defect distributions in multicrystalline silicon on solar cell performance

We describe results of our theoretical and experimental studies performed to investigate the influence of defects and defect distributions in multicrystalline silicon (mc-Si) wafers on the solar cell´s performance. Dislocation distributions were measured on wafers from various bricks of a mc-Si ingot. Solar cells were fabricated on sister wafers and characterized by a variety of methods. Cell performance can be accurately predicted from dislocation distribution of a mc-Si wafer using local N/P junction characteristics in a distributed network model. This analysis is applied to investigate changes in cell performance caused by dislocation propagation within a brick of mc-Si ingot. The theoretical results agree well with the measured performance of cells fabricated on wafers taken from different places in a brick.