CURRENT STATUS OF TECHNOLOGIES FOR INDUSTRIAL EMITTER WRAP-THROUGH SOLAR CELLS

摘要

Emitter wrap-through solar cells are being fabricated in pilot production at Advent Solar using multicrystalline silicon wafers and standard industrial processes. The short-circuit current densities around 36 mA/cm~2 are achieved primarily because of the absence of front grid or busbar shadowing. Open-circuit voltage improves with decreasing wafer thickness—the sensitivity of this dependence is greater for low lifetime silicon. The fill factor remains an area for improvement with series resistance reduction by such means as improved grid conductivity, metallization design, and emitter through-hole resistance. Standard production cells exceed 15.2% efficiency and some immediate paths to greater than 16% efficient, production-worthy emitter wrap-through cells are described.