As described in the previous section there are three stages for stress generation during film growth, but a careful analysis leads to some simplifications. The compressive stress created by nucleation can be neglected for engineering purposes, because of its small contribution to the eventual state of the thin film. Therefore, coalescence and grain growth define the residual stress of the film. For low adatom mobility metals, the effects of grain growth on the stress can also be ignored and the final state is solely determined by the stress developed during coalescence.
The importance of coalescence stress is reflected in the variety of models in the literature, which attempt to explain it . Three models are broadly known in the scientific community either by their precision or by their physical meaning. Each model will be explicitly presented in the following sections.