CALCULATION OF ION-SCATTERING YIELDS FROM SIMULATED INTERMETALLIC SURFACES - NI-AL(110)

A recently developed formalism for calculating ion-scattering yields f rom simulated crystal surfaces has been extended to the case of bimeta llic surfaces. MeV He+ scattering yields are calculated for thin Ni fi lms reacting with Al(110) surfaces. Interatomic potentials based on th e embedded-atom method are used in a Monte Carlo approach to simulate the evolution of the Ni-Al interface asa function of Ni coverage. The calculated ion-scattering yields are in good quantitative agreement wi th the measured yields, showing two distinct stages of reaction and ov erlayer growth. Limitations of the simulation and measurement methods are discussed.