First-principles investigation of metal/oxide contacts and related metal/group-IV interfaces

Density-functional band-structure calculations have been carried out for two types of material combinations at heterophase boundaries in order to characterise the main influence factors on adhesion.
Strong binding at heterophase interfaces is often related to a favourable and directed electron redistribution in the vicinity of the boundary plane.
The propensity for such redistributions is reflected in materials parameters such as electronegativities, polarisabilities and the differences between the values of the two sides of the interface. Strong adhesion is indirectly also related to the lattice matching or mismatch, because that influences the density of suitable in-teraction sites in the boundary plane.
Finally, fixed local charges, which are characteristic for ionic compounds, introduce additional Coulomb and image charge interactions. The present comparison aims at assessing those latter interactions by comparing material combinations with one ionic partner to completely non-ionic combinations.