Progress of large area 18%-PEBSCO - silicon solar cells

Developments and progress of the PEBSCO-technology applied on large area (about 150 cm/sup 2/) solar cells regarding advanced emitter profiles in combination with suitable surface passivation, regarding features enabled by the boron back surface field and regarding improved screen printing metallization are reported. Moreover, improvements of the cell fabrication technology become effective in particular on silicon with high minority carrier lifetimes, e.g. monocrystalline float zone grown silicon. The absence of light induced degradation and the additional fundamental high minority carrier lifetimes favour float zone silicon wafers for stable high efficiency solar cells. Even by using modified Cz-cell fabrication processes, first large area (150 cm/sup 2/) screen printed solar cells on float zone wafers with stable efficiencies of 18% have been achieved. With respect to back contact solar cell concepts the behavior of such cells under illumination from the rearside was investigated.