Published online by Cambridge University Press: 01 February 2011
The physics and mechanics of a fracture toughness measurement technique for low-k films are described. It has been observed experimentally that it is possible to generate reproducible stable cracks at indentation sites in thin low-k films using cube-corner indentation. The fracture response depends on the film thickness and follows no simple scaling laws. The physics of a model that takes into account the stress fields from indentation and film stress, with particular attention paid to the Poisson's ratio of the film, are described. The model is able to predict the changes in observables when the film thickness is changed, which allows one to estimate film toughness independent of the configuration of the material.