Properties of Bi-Based Glass Powders with Low Glass Transition Temperature, Spherical Shape and Fine Size as the Additive of Silver Conducting Paste

Bi-based glass powders with low glass transition temperature of 373 degrees C for silver paste were directly prepared by spray pyrolysis at 1200 degrees C. The mean size and geometric standard deviation of the glass powders with spherical shape were 0.75 mu m and 1.3. The glass film formed from the prepared glass powders had clean surface and cross-section at a firing temperature of 450 degrees C. Adhesion properties between the silver electrode and glass substrate improved with increase of the addition amount of glass powders into silver paste and the firing temperatures. The addition of glass powders decreased the sheet resistances of the silver conducting films irrespective of firing temperatures. The sheet resistances of silver conducting films were changed from 7.7 to 5.5 mu Omega cm when the glass content added to the silver paste were changed from 0 to 5 wt. % at a firing temperature of 550 degrees C.