Thickness dependent phase stability of epitaxial metal films

摘要

In this letter a simple model to account for the thickness and structure dependent cohesive energy of metallic films is developed to predict the phase stability of epitaxial metal films on metallic substrates. After calculation, it is shown that the substrates have an important effect to the phase stability of films and that the films may have a trend to follow the structure of the substrates below a critical thickness hcritical, which can be determined by the present model. A comparison of the model predictions with available experimental data is carried out and the predictions are in agreement with the experimental results.