Hydrogen implantation of silicon sheets

The impact of hydrogen passivation by means of ion implantation has been studied. The surface recombination velocity dramatically increases due to the passivation and cannot be restored. This will limit very high efficiencies in poplycrystalline silicon solar cells. The passivation depth of both grain boundaries and the individual grains depend on the trap density of the material and on the diffusion profile of the hydrogen. (ISE)