High-lifetime kerfless silicon wafers

Thin kerfless crystalline silicon wafers have long been pursued to reduce the manufacturing cost of crystalline silicon photovoltaics. However, although the potential for wafer cost reductions provided by these technologies is significant, the manufacturing cost of modules is most sensitive to power conversion efficiency. Therefore, a kerfless silicon wafer must be of sufficient electrical quality to support high device efficiencies for maximum economic impact. We present both p-type and n-type epitaxially grown kerfless material with high electrical quality. Carrier lifetimes > 300 μs effective and > 800 μs estimated bulk at a 10¹⁵ cm^-3 injection level after gettering are reported for p-type material. This material has a single-crystal structure and does not appear to be limited by interstitial iron. With n-type material, effective lifetimes > 850 μs at a 10¹⁵ cm^-3 injection level after gettering are presented.