A simple model was presented for intrinsic stress generation in thin films resulting from surface stress effects. This mechanism can explain the origin of compressive stresses often observed during island growth prior to coalescence, as well as intrinsic compressive stresses reported for certain continuous, fully grown films. In some cases, surface stress effects may contribute to a sudden change in the intrinsic stress during island coalescence.

Experimental results are presented for stress evolution, in vacuum and electrolyte, for the first monolayer of Cu on Au(111). In electrolyte the monolayer is pseudomorphic and the stress-thickness change is -0.60 N/m, while conventional epitaxy theory predicts a value of +7.76 N/m. In vacuum, the monolayer is incoherent with the underlying gold. Using a combination of first-principles based calculations and molecular dynamic simulations we analyzed these results and demonstrate that in electrolyte, overlayer coherency is maintained owing to anion adsorption.

We present the first set of results measuring the change in interfacial free energy and surface stress for Au(111) electrodes in an electrolyte containing a nonspecifically adsorbing anion and compare this behavior to that in an electrolyte containing an anion known to undergo specific adsorption. Generally, we find that the surface stress is more sensitive to changes in electrode potential and adsorption then the interfacial free energy. The results obtained in fluoride electrolytes are compared to the predictions of a thermodynamic analysis.

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We have performed computer simulation studies on the 22×√3 surface reconstruction of Au(111). This reconstruction involves a uniaxial contraction of the top monolayer corresponding to a surface strain of about 4.3% and has been observed to be the stable structure for clean surfaces at low temperatures. A continuum model yields a stability criterion that depends on the knowledge of a small number of measurable physical quantities: surface stress f, surface free energy γ, lattice parameter a0 and shear modulus µ. The simulations using EAM potentials accurately reproduce many observed features of the reconstruction and tend to support the continuum model and the resulting stability criterion.

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