Size-controlled Bi-based glass powders prepared by spray pyrolysis as inorganic additives for silver electrode

Bi-based glass powders as additive for silver conducting pastes were prepared by spray pyrolysis. The glass powders formed from the spray solution with low concentration of 0.025 M had bimodal size distribution with nanometer and submicron sizes. However, glass powders with spherical shape and narrow size distribution were prepared from the spray solutions with concentrations of 0.05 and 0.5 M. The mean size of the glass powders increased from 0.34 to 0.7 μm when the concentrations of the spray solutions changed from 0.05 to 0.5 M. The glass transition temperature of the glass powders with the mean size of 0.34 and 0.70 μm were 382 and 396 °C, respectively. The glass layers fired at 450 °C had clean surfaces irrespective of the mean size of the glass powders. Silver conducting films were formed by melting of the silver powders irrespective of the mean sizes of the glass powders at firing temperatures between 400 and 500 °C. The specific resistances of the silver conducting films change from 3.13 to 4.03 μΩ cm according to the mean size of the glass powders at a firing temperature of 500 °C.