Gliding at interface during thin film buckling: A coupled atomistic/elastic approach

The buckling of a Cu thin film deposited on a stiff W substrate is studied by means of molecular static simulations using interatomic potentials. The buckling of a preexisting delaminated part of the film is observed under a uniaxial strain without any further decohesion of the interface. A sliding phenomenon is also observed at the edges of the buckle which can be interpreted in terms of glide of misfit dislocations. Integrating this sliding effect in the Föppl-von Kármán theory of thin plates, a modified analytical expression for the deflection of the film has been derived which fits with the deflection obtained from the simulations.