Thick-film pastes containing lead- and tellurium-oxides, and their use in the manufacture of semiconductor devices

A thick-film paste composition for use in forming an electrical connection in a photovoltaic device comprising a semiconductor substrate having at least one insulating layer on a main surface thereof, the composition comprising:

• a) 95.5 to 99.5% by weight of an electrically conductive metal or derivative thereof, based on total solids in the composition;
• b) 0.5 to 4.5% by weight based on solids of a lead-tellurium-oxide, wherein the mole ratio of lead to tellurium in the lead-tellurium-oxide is between 5/95 and 95/5, the lead-tellurium oxide comprises at most 67.72% of PbO by weight of the lead-tellurium-oxide and comprises at least 32.28% of TeO2 by weight of the lead-tellurium-oxide, and the lead-tellurium-oxide comprises one or more of P2O5, Al2O3, TiO2, Cr2O3, Mn2O3, Fe2O3, CoO, Co2O3, NiO, CuO, Ga2O3, GeO2, Rb2O, Cs2O, SrO, BaO, In2O3, SnO2, Sb2O3, and CeO2 in an amount ranging from greater than 0 to less than 9% by weight of the lead-tellurium oxide, and the lead-tellurium oxide is at least partially crystalline;
• and
• c) an organic medium;
• and wherein the thick-film paste, when fired, is capable of penetrating the at least one insulating layer.