Thermal properties of glass frit and effects on Si solar cells

Glass frit is critical for the Ag/Si contact formation and performances of Si solar cells. Lead–boron–silicate glasses were prepared through traditional melt-quenching method. The influences of softening temperature (Tf), as an important point of viscosity, on the Ag grid microstructures and performances of cells were discussed in detail. SEM images showed that Ag powders sintered well with decreasing Tf, resulting in improved performances of cells. The decreasing of Tf also affected the corrosion of SiNx coating, the amount and size of Ag re-crystallites, and glass layer thickness between Ag gridline bulk and Si emitter surface. Therefore, glass frit Tf is the key factor for optimizing performances of cells.