Thermal strain offset strategy for fabrication of glass-ceramic to metal seals with high-reliability

Excessive thermal stress in the glass-ceramics to metal seals (GCtM) is known to be inimical to the reliability of the related electrical components and thus typically avoided during the sealing process. Quartz, a linear high-expansion material, has long attracted extensive attentions in GCtM seals, ascribed to its ability to ameliorate the thermal stress in the sealing component. However, the quartz crystallization in the lithium silicate recrystallization glass-ceramics need for a series of complex and cumbersome thermal profiles, especially including a rapid cooling process (>70 °C/min), in the conventional method. Here, we disclose a key finding that a small amount of quartz seed could promotes quartz crystallization at a slower cooling rate and higher temperatures. To counter the problem mentioned above, a thermal strain offset strategy is proposed, which embodies a model to predict the thermal expansion behaviors at different temperatures and the controlled growth of quartz. Consequently, a novel glass-ceramics with near-linear thermal strain have been obtained, notably through a facile and high-efficient thermal profile. More surprisingly, the improved sealing glass exhibits a fluidity similar to that of the original material and the distinctive ability to ameliorate the thermal stress at elevated temperature. This work sheds light on developing high-reliable and cost-effective manufacture method for industrial production of the related electronic component.