Novel processes for simplified buried contact solar cells

This paper describes two novel solar cell rear-surface technologies for high-efficiency, thin-wafer, buried contact (BC) solar cells. The first is a laser-formed aluminium-silicon alloy process that is suitable for the fabrication of a low resistance, low-recombination, semi-transparent rear grid electrode. Initial solar cells fabricated with such a rear grid have reached efficiencies of 15% with little optimisation. The second is pigmented diffuse reflectors for light trapping in textured crystalline silicon wafers. These materials exhibit high and broadband reflectivity and are potentially low cost