Investigation of the glass forming regularity and thermal behavior of lead-free V2O5-TeO2-RO (R = Ca, Sr, Ba) low temperature sealing glass for electronics packaging

Lead-free V2O5-TeO2 glass systems are promising new sealant materials for electronics vacuum packaging, with low-melting temperature and unique light absorption. The glass forming regularity, structure and corresponding properties of the V2O5-TeO2-RO (R=Ca, Sr, Ba) glass system are systematically studied and analyzed in this paper. The results show that there is a wide glass forming region for the V2O5-TeO2-RO glass system, and with the increase of TeO2/V2O5 molar ratio, the thermal stability of V2O5-TeO2-SrO glass with the RO content of 20 mol% increases and the coefficient of thermal expansion increase from 11.2 to 15.86 × 10–6/°C due to transformation process of glass network structure from the [VO4] to transition state [TeO3 + 1] and [TeO3] group. The higher initial crystallization temperature of 40 mol%V2O5-40 mol%TeO2-20 mol%SrO glass is conducive to the flow of the glass slurry during the sealing process, obtaining a sealing device with good airtightness at extremely low temperatures of 350 °C.