Tensile straining of a cross-sectional Al/polyimide was performed in a transmission electron microscope. The tensile deformation of Al was accomplished mainly by dislocations emitted from the film surface, which glide and impinge on the Al/polyimide interface. During further straining the interfacial dislocations disappeared, indicating dislocation core spreading, whereas threading dislocations moved towards the film surface. While the Al/polyimide interface remains flat and becomes depleted of dislocations, the Al surface becomes increasingly rough accompanied by a noticeable increase in dislocation density.

Dislocation Plasticity of Al Film on Polyimide Investigated by Cross-Sectional in situ Transmission Electron Microscopy Straining. S.H.Oh, C.Rentenberger, J.Im, C.Motz, D.Kiener, H.P.Karnthaler, G.Dehm: Scripta Materialia, 2011, 65[5], 456-9