Transparencies of dielectric layers formed from size-controlled Bi-based glass powders obtained by spray pyrolysis

Submicron-size Bi-based glass powders were directly prepared by high-temperature spray pyrolysis. The mean sizes of the Bi-based glass powders were changed from 0.48 to 0.91μm by changing the concentrations of spray solution. The dielectric layers formed from the Bi-based glass powders with fine size had higher transparencies than those of the dielectric layers formed from the Bi-based glass powders with large size. The transparencies of the dielectric layers formed from the glass powders obtained by spray pyrolysis from spray solution of 0.05M decreased from 94 to 67% when the firing temperatures of the dielectric layers were changed from 580 to 500 °C. At the same firing temperatures, the transparencies of the dielectric layers formed from the glass powders obtained by spray pyrolysis from spray solution of 0.5M decreased from 83 to 28%. The dielectric layers formed from the glass powders with fine size had dense and homogeneous structures even at low firing temperatures.