Tensile strength of gold nanointerconnects without the influence of strain gradients

Gold is an ideal material for wires and electrodes on the nanoscale because of its corrosion resistance and biocompatibility. For system integration the mechanical properties of gold nanowires are highly important. In this paper, a study on the deformation behavior of parallel line arrays of gold on polyimide substrates is presented. Arrays of 45–60 nm nanolines were produced by extreme ultraviolet interference lithography, evaporation of gold and a subsequent lift-off process. Tensile testing of these samples was performed by using an in situ synchrotron-based technique, which allows for the fast acquisition of diffraction peaks. The samples show yield stresses of about 400 MPa. This is comparable to thin films of similar thickness, but significantly lower than previously reported results on single electrodeposited wires deformed in bending. The differences are explained in terms of strain gradient plasticity theory.