Thin-Film Polycrystalline Silicon Solar Cells Formed by Diode Laser Crystallisation

Abstract

Polycrystalline silicon films of 10 μm thickness are formed on glass in a single-step CW diode laser crystallisation process, creating large crystal grains up to 1 mm wide and 10 mm long. Solar cells are formed on the layers by employing a rear point contacting scheme. Intermediate layers between the glass and the silicon are shown to heavily influence the cell characteristics. A stack of silicon oxide / silicon nitride / silicon oxide has produced the best cell efficiency so far of 8.4 % with open-circuit voltage of 557 mV. With simple optimisation of the contacting scheme, 10 % efficient cells are expected in the near future.