Trace elemental analysis of precipitates in multicrystalline silicon and investigation of solar cell shunting
Abstract
The main aims of the photovoltaic industry are an enhancement of solar cell efficiency, the reduction of production costs and also to improve the production yield. The presence of various kinds of precipitates in block-cast multicrystalline Si for wafer-based solar cell production has a significant impact on the subsequent process technology. In this work the microstructural properties of SiC and Si3N4 precipitates as well as SiC filaments on grain boundaries are investigated with NIR microscopy, SEM and TEM studies. The elemental composition is analyzed with the help of ToF-SIMS and the electrical properties are investigated by LIT, BS-EBIC and 4-point probing. Our results contribute to new insights in solar cell shunting processes.
