Test bed for mechanical characterization of nanowires

Nanowires are one-dimensional solids that are deemed to be the building-block materials for next-generation sensors and actuators. Owing to their unique length scale, they exhibit superior mechanical properties and other length-scale-dependent phenomena. Most of these are challenging to explore, owing to the difficulties in specimen preparation, manipulation, and the requirement of high-resolution force and displacement sensing. To address these issues, a micromechanical device for uniaxial mechanical testing of single nanowires and nanotubes is used here. The device has 10 nN force and 1 nm displacement resolution and its small size (2 ×1 mm) allows for in situ experimentation inside analytical chambers, such as the electron microscopes. A microscale pick-and-place technique is presented as a generic specimen preparation and manipulation method for testing single nanowires. Preliminary results on zinc oxide nanowires show the Young's modulus and fracture strain to be about 76 GPa and 8 per cent respectively.