Structure regulation and performance optimization of low-dielectric borosilicate sealing glass for Kovar alloy

To enhance signal transmission speed and reduce signal attenuation, the glass used for electronic packaging must have a low dielectric constant. This study explores the impact of increasing B₂O₃ content on the structure and performance of low-dielectric sealing glasses. Structural analysis shows that an increase in B₂O₃ content leads to the gradual replacement of [SiO₄] units by [BO₃] units in the sealing glass, and the porosity inside the sealing glass increases gradually. This results in a more loose structure, thereby effectively reducing the dielectric constant and improving its wettability on Kovar alloy. The sealing glass with a SiO₂/B₂O₃ ratio of 1.71 exhibits the optimal performance: it has a dielectric constant of approximately 3.38 in the Ku band (12–17.5 GHz), a shear strength of 3.306 MPa on Kovar alloy, and a weight loss rate of 0.00204 g·cm^-2 after being immersed in water at 90 °C for 12 h. While maintaining a low dielectric constant, it also possesses favorable thermal, mechanical, and water-resistant properties. This study provides a practical solution for designing high-performance sealing glasses for high-frequency microelectronics applications.