Triangular Dislocation Loop Model for Surface Displacement in Indented Thin Films

Abstract

The surface displacement of the indented layered composite has been observed by AFM and TEM, and the elastic recovery due to the indentation residual stress is compared with the prediction of the triangular dislocation model. At the shoulders of the indentation, the upheaval of Al-4wt%Cu film is smoothly connected, whereas that of Al2Cu film is localized as the intensive sheared displacement. The magnitude of the elastic recovery in film/substrate composite is larger than the predicted value, which might be attributed to the repulsive interaction between the glide dislocations and the hard Si substrate.