We have used interfacial force microscopy (IFM) to monitor the mechanical deformation of single nanometer-size grains in Au thin films. Our results show that protruding grains, which represent early-stage delamination, display multiple deformation mechanisms including grain-boundary sliding and intragranular plasticity. The unprecedented load-displacement control capability of the IFM provides data that are used for the first time to quantitatively distinguish and evaluate individual deformation processes.

• Received 6 July 1993

DOI:https://doi.org/10.1103/PhysRevLett.71.3319