Spray pyrolysis of organo-metallic compounds for passivation layers on semicrystalline silicon solar cells

Semicrystalline silicon solar cells were applied with thin layers of glass deposited by spray pyrolysis of metal-organic compounds and examined for their usefulness as surface passivation layers. These as-deposited compounds are similar to those used in thick-film ink compositions and permit fire-through of screen-printed contacts. In the setup of the spraying system, a moving gantry permits relatively uniform layers of various boron organic liquids to be applied to a moving substrate. A simple schematic of this equipment is shown. Both single-crystal and semicrystalline silicon wafers with base resistivities of 1-2 Omega cm and thicknesses of 0.3-0.4 mm were used. Both groups showed substantial improvement in solar cell voltage.