Metal to glass sealing using glass powder: Ion induced crystallization of glass

In this study, we investigated bonding mechanism of a metal foil with glass substrate. We used glass powder to enhance surface area and promote diffusion in the interface. The metal/glass powder/glass assembly was annealed at 600 degrees C for 1 h and adhesion process was monitored. Using transmission electron microscope, element mapping, Raman and energy dispersive X-ray spectroscopy analyses we traced elements' migration and estimated bonding mechanism. Cross-diffusion of atoms/ions from metal to glass and in the reverse direction occurred. We estimated that diffusion of iron cations toward the glass substrates induced crystallization of the glass and dendritic crystals were formed.