Economical and ecological aspects of plasma processing for industrial solar cell fabrication

Plasma processing represents one possible solution to meet the requirements necessary for the realization of novel cell concepts suitable for larger and thinner wafers. Within this work, economical and ecological aspects of the new technology have been considered. The high global warming potential (GWP) of the perfluorocompound etching gases necessitates waste gas abatement systems with high destruction and removal efficiencies. Plasma conversion turned out to be the most adequate and flexible solution. With an effective waste gas treatment, additional CO² emissions due to plasma processing can be balanced not to exceed 6 month operating time of a PV system. Based on a dry, completely in-line process scheme, cost of ownership calculations show the cost reduction potential of plasma processing for mc-Si wafers compared to wet chemical state-of-the-art processing.