Reduction in contact resistivity of Ag thick-film conductor on SiN x -coated Si wafer for solar cell using lead tellurite glass frit

In an application for metallization contact of Ag thick-film conductor onto the SiNx-coated Si wafer for solar cells, we examined the wettability, reactivity, microstructure, and electrical contact of two kinds of glass frits: lead borosilicate and lead tellurite. The lead tellurite frit exhibited superior wettability on Si and higher reactivity with SiNx and formed the thinner glass layer between Ag rich layer and Si for firing the Ag thick-film paste at 750 °C, resulting in better conductive contacts. The contact resistivity of Ag thick-film conductor using lead tellurite glass frit was less than one-tenth of that using lead borosilicate glass frit.