"We can now manipulate metallic glasses on extremely small scales, which were inaccessible in the past," team member Golden Kumar told nanotechweb.org. "These glasses could be ideal materials for small-scale applications due to their superior mechanical and homogenous properties."

Nanomoulding metallic glasses will have an important impact on nanoimprint lithography, which is regarded as the next-generation tool for nanoscale pattering, adds Kumar. Current nanoimprint technology relies on silicon-based moulds that are expensive to make and are not very durable. Nanoscale patterning such moulds also requires expensive and low-throughput electron-beam lithography.

The Yale researchers made their metallic glass templates by simple embossing techniques thanks to the fact that newly developed metallic glasses flow like plastics at moderately high temperatures. The metallic glass casts are stronger than silicon-based ones, can be massively replicated and are also reusable because features can be erased and the mould re-sculpted.

Kumar says that the moulds could be used as templates for nanoimprinting, rewritable high-density data storage, patterned surfaces for biomedical applications and photolithographic masks. "As well as these technological applications, the ability to precisely create metallic glass structures on the nanometre scale allows scientists to study the effects of size on the properties of amorphous materials – a subject that is hotly debated in the amorphous metal community," added team leader Jan Schroers.

The researchers would now like to imprint even smaller features and study wetting phenomena between the different mould materials and metallic glasses. This will be the key to successful nanomoulding with metallic glasses, they explain.

The work was reported in Nature.