Effect of nickel on the lifetime of charge carriers in silicon solar cells
Abstract
It has been shown experimentally that nickel clusters on the surface of a silicon sample contain a large amount of oxygen and recombination impurities --- Cu, Fe, Cr, and so shows good gettering properties of clusters. The optimum temperature of nickel diffusion into silicon is determined as 800-850 o C. Doping with impurity nickel atoms with the formation of clusters makes it possible to increase the lifetime of nonequilibrium charge carriers in the base of a solar cell by up to 2 times, while the formation of a nickel-enriched region in the face layer is more efficient. It is shown that the effect of additional doping with nickel weakly depends on the sequence of the processes of nickel diffusion and the creation of a working p-n-junction. Keywords: silicon solar cells, nickel diffusion, nonequilibrium charge carriers, gettering, p-n junction.