Focused ion beam preparation of microbeams for in situ mechanical analysis of electroplated nanotwinned copper with probe type indenters

A site‐specific xenon plasma focused ion beam preparation technique for microcantilever samples (1 μm ‐ 20 μm width and 1:10 aspect ratio) is presented. The novelty of the methodology is the use of a chunk lift‐out onto a clean silicon wafer to facilitate easy access of a low‐cost probe type indenter which provides bending force measurement. The lift‐out method allows sufficient room for the indenter and a line of sight for the electron beam to enable displacement measurement. An electroplated nanotwinned copper (NTC) was cut to a 3 × 3 × 25 μm micro‐beam and in‐situ mechanically tested using the developed technique. It demonstrated measured values of Youngs modulus of 78.7 ± 11 GPa and flow stress of 0.80 ± 0.05 GPa, which is within the ranges reported in the literature.