Buckling-based measurements of mechanical moduli of thin films

The buckling-based measurement of mechanical properties of material is reviewed here, which is a very useful technique for the characterization of thin films, nano- or molecular-scale materials, etc. This method is shown to be useful to measure elastic moduli of various thin films such as polymers, polyelectrolyte multilayers (PEM), single-wall carbon nanotubes (SWNT) and millimeter-thick polymer network substrates. Further, it is also shown that the mechanical properties of various organic electronic materials, which may find wide applications in flexible and/or stretchable electronic devices, can be measured by the buckling method. Due to its fast, simple nature, the method can be extended to many other materials, especially to materials existing in thin film form only. The method would be a valuable, complementary technique in mechanical characterization of materials to be added to existing methods such as tensile testing, nano-indentation, and other methods.