Laser shock forming of metal nanostructures with ultrafine gaps

The nanogaps between metal nanostructures are of great importance in nanotechnology. However, low cost and high precision fabrication of such nanogaps is still a difficult problem. In this paper, a method combining nanosecond laser shock and flexible metal film is proposed to form ultrafine gaps between metal nanostructures. The forming mechanism of ultrafine gaps between metal nanostructures was revealed by studying the superplastic deformation, spatiotemporal evolution of stress and strain, and cooperative deformation of the flexible metal thin film and metal nanostructures under laser shock. On the basis of the mechanism study, the effects of laser parameters and gold nanoparticle size on the forming of ultrafine gaps were further studied, so as to achieve high precision forming of ultrafine gaps (<10n m) between metal nanostructures.