Understanding of High-Throughput Rapid Thermal Firing of Screen-Printed Contacts to Large-Area Cast Multicrystalline Si Solar Cells

In this paper, we investigate the conditions that are necessary to produce high-quality screen-printed metal contacts to large-area cast multicrystalline Si solar cells using a high-throughput infrared conveyer belt furnace. We show that high sinter ramp rates produce a back-surface recombination velocity of ~400 cm/s and the most homogeneous Al back-surface field. We also show that the short sinter dwell time produces a thin Ag/Si interfacial glass layer; optimal bulk defect hydrogenation, as indicated by final bulk lifetime improvements; and low Ag specific contact resistance. The fundamental research and understanding applied here produces high fill factors, low series resistance, and high efficiency.