Adhesion at a heterophase interface: First-principles study of Mo(001)/MoSi<inf>2</inf>(001)

Abstract

The bonding characteristics, interfacial energetics, and electronic structure associated with adhesion at the Mo-MoSi2(001) heterophase interface are investigated using the first-principles, self-consistent local orbital method. We found both the adhesive energy and peak interfacial strength for the interface to be 10%-15% smaller than the respective values for cleavage along the (001) planes in crystalline Mo and MoSi2. The equilibrium interlayer separation between Mo and MoSi2 is found to lie between the interplanar spacings of crystalline Mo and MoSi2. The interfacial adhesive bonding is attributable to the combination of a nearly uniform band of charge accumulation at the interface and directional charge accumulation between atoms across the interface. These first-principles calculations demonstrate that the universal-binding-energy relation can be extended to describe adhesion between dissimilar materials. © 1994 Kluwer Academic Publishers.