Quantum size effects in nanoscale metallic structures

Spatial confinement of electrons in a nanoscale metallic structure gives rise to a set of standing wave states and quantized energy spectra. The quantized nature of the electrons and the enhanced boundary scattering could seriously affect the electron transport in future nanoscale interconnects. As revealed by scanning tunnelling microscopy, such quantum size effect also plays a competing role along side the classical thermodynamic effect in the shape relaxation of a metallic nanostructure. In particular, it leads to very unusual mass transport behaviours. Like the electron migration, such effect may have significant impact on the stability of nanoscale metal interconnects.