Investigation on structure and properties of nitride-tin-boron-fluorophosphate glass for low-temperature sealing

Glass with composition of 45 P2O5–53SnF2–2B2O3 (mol%) was prepared by using the one-step melt quenching method. The effect of nitrogen on tin-boron-fluorophosphate glass was investigated. Full characterizations have been carried out by the XRD and FTIR, as well as by the XPS spectroscopies. Infrared results reflected that intensity of the P = O bonds and bridging oxygen declined since the oxygen was replaced by nitrogen. XPS results suggested transformation in the bond type of glass network. The new P-N and P = N bonds was proved to exist in structure. Differential scanning calorimetry (DSC) of glass showed that the transition temperature increased with the increasing NH4H2PO4 content. Similar tendency was observed in results of thermal expansion curves (TEC), Tf =160.1℃. The weight loss of bulk glass decreased as the concentration of NH4H2PO4 increased. This work proves that the nitride tin-boron-fluorophosphate with satisfied properties has potential to be low-temperature sealing material.