Characterization of metallized ceramic interfaces

Using a variety of surface analytical tools, the interfaces of several metal-ceramic composites have been characterized. Three processes that lead to the bonding of a metallizing to a ceramic substrate are illustrated. When a pure refractory metallizing is deposited onto a 94% Al₂O₃, bonding is achieved by glass migrating from the ceramic into the metallizing during firing. During cooling, the glass forms a mechanical-chemical bond between the ceramic and metallizing. In order to achieve bonding to a 99⁺% Al₂O₃ or 99⁺% BeO, the metallizing itself must contain a sufficient quantity of glass for wetting the ceramic, or be capable of forming a direct chemical bond to the ceramic.