Cz bifacial solar cells

High efficiencies have been achieved with bifacial solar cells made on FZ silicon. In the adaptation of the process to the more commonly used Cz material, attention has been paid to the influence of thermal processing on Cz, trying to avoid internal gettering effects related to oxygen precipitation. Lifetime measurements at different steps of the process have been carried out to quantify this influence. Reduction of "thermal load" by growth of a thin passivating oxide and deposition of a double antireflecting coating gives 17.7% when illuminated from the n/sup +/ side and 15.2% when illuminated from the p/sup +/ one.