Indirect-Bonded Metallization of Aluminum Nitride

Abstract

AbstractThe use of aluminum nitride (AIN) as a substrate and packaging material for microcircuit applications is of present interest due to its many advantageous physical properties. A limitation to the widespread use of AIN is the lack of an adequate metallization system. The most common method of achieving high-integrity metallized ceramics is through the use of indirect-bonded metallizations. A wide range of intermediate bonding materials are used, for example glasses, oxide mixtures, and active metals. In this paper, the indirect-bonded metallization of AIN will be reviewed and discussed. Requirements which must be considered in producing successful metallizations include; wetting of the substrate and the metal by the intermediate phase and the reactivity between the intermediate phase and the substrate. The reactions which occur in many of the systems considered can be predicted by examination of thermodynamic data.