19% efficient n-type Czochralski silicon solar cells with screen-printed aluminium-alloyed rear emitter

High and stable lifetimes recently reported for n-type silicon materials are an important and promising prerequisite for innovative solar cells. To exploit the advantages of the excellent electrical properties of n-type Si wafers for manufacturing simple and industrially feasible high-efficiency solar cells, we focus on back junction n(+)np(+) solar cells featuring an easy-to-fabricate full-area screen-printed aluminium-alloyed rear p(+) emitter. Independently confirmed record-high efficiencies have been achieved on n-type phosphorus-doped Czochralski-grown silicon material: 18.9% for laboratory-type n(+)np(+) solar cells (4 cm(2)) with shadow-mask evaporated front contact grid and 17.0% for front and rear screen-printed industrial-type cells (100 cm(2)). The electrical cell parameters were found to be perfectly stable under illumination. Copyright (C) 2006 John Wiley & Sons, Ltd.