Tailoring the sealing properties of TiO2-CaO-SrO-B2O3-SiO2 glass-ceramic seals: Thermal properties, chemical compatibility and electrical property

In this paper, TiO2 is added to CaO-SrO-B2O3-SiO2 sealing system to tailor the sealing properties of glass-ceramic seals. The coefficient of thermal expansion (CTE) of quenched glasses and glass-ceramics (held at 750 °C for 100 h) does not change significantly with the addition of TiO2; whereas, the glass stability (ΔTxg = Tx − Tg) decreases systematically with increasing TiO2. The addition of TiO2 accelerates the crystallization of sealing glasses. The formation of Sr-containing phase, e.g., Sr(TiO3), contributes to the improved chemical compatibility as well as the increase in conductivity of sealing glasses (e.g., from 7.9 × 10−8 S cm−1 to 6.9 × 10−5 S cm−1 at 800 °C). In addition, the good bonding is observed at the interface between Cr-containing interconnect (430SS) and glasses containing 4-8 mole % TiO2, held at 750 °C for 100 h.