Effect of structure change on thermal and dielectric characteristics in low-temperature firing Bi₂O₃-B₂O ₃-ZnO glasses

In a Bi₂O₃-B₂O₃-ZnO glass system, glass structure change, sintering behavior and resultant physical characteristics of the glass were examined when various amounts of Bi ₂O₃ and ZnO mixture were added. When the total amount of Bi₂O₃ and ZnO was below 30 mol%, a phase separation occurred and homogeneous glass was not obtained. The fraction of four-coordinated borons (BO₄) was highest when the total amount of Bi₂O₃ and ZnO was 50mol%. Further addition over 50 mol% induced a borate anomaly phenomenon in the glass, which resulted in the decrease in BO₄ fraction. The sintering temperature and glass transition temperature decreased as the amount of Bi₂O₃ and ZnO increased. The thermal expansion coefficient and dielectric constant of the specimens were also examined.