A new on chip nanomechanical testing concept applied to ductile and brittle thin film materials

The measurement of the mechanical properties of submicron sized specimens is extremely challenging due to difficulties for manipulating samples, for applying small load and for extracting accurate stresses and strains. A novel, versatile concept of micromachines has been developed to measure the mechanical response, up to large strains and fracture, of films, beams or tubes, with dimensions ranging between 10 to 1000 nm, allowing multiple loading configurations and geometries. This new concept relies on microfabrication techniques destined to the production of microelectronic devices and MEMS. The first idea is to use internal stresses to actuate and impose the load to the tested sample which is directly deposited on a patterned substrate. The second idea is to multiply elementary machines rather than to build on single complex multi-purpose micromachine, see Fig. 1. The stress and strain are directly inferred from a local displacement measurement. Other loading configurations than simple tension have been designed such as shear, biaxial, compression and double cantilever opening.