The motion of dislocations during the temperature cycling of Al films which were passivated with SiO2 layers was studied by means of in situ transmission electron microscopy. The films were cycled between room temperature and 450C. Wedge-shaped cross-sectional transmission electron microscopic samples were used to retain the constraint of a Si substrate. As well as interactions between dislocations and interfaces, the movement of threading dislocations within the constrained Al film was also observed. This provided experimental confirmation of the threading dislocation motion which was the basis of current explanations for the high yield strength of thin films.

in situ Transmission Electron Microscopy Investigation of Threading Dislocation Motion in Passivated Thin Aluminium Films. R.M.Keller-Flaig, M.Legros, W.Sigle, A.Gouldstone, K.I.Hemker, S.Suresh, E.Arzt: Journal of Materials Research, 1999, 14[14], 4673-6