Connection of Glass and Kovar Alloy Based on Anodic Bonding

Anodic bonding was used to successfully realize the connection between Borofloat33 (BF33) glass and Kovar alloy. The bonding current change shows that during bonding process the current rapidly increases to the peak value, and then decreases exponentially, and the peak value of the bonding current increases with the increase of the bonding temperature and voltage. Scanning electron microscope (SEM) was used to observe the micromorphology of the Glass-Kovar interface. It is found that the bonding interface is good. Under the condition of 500 ℃/1000 V, the thickness of the Na⁺ depletion layer at the Glass-Kovar interface is about 100 nm. The tensile test at ambient temperature shows that the shear strength of the sample increases with the increase of the bonding temperature and voltage, and the fracture always occurs at the glass substrate.