Engineers revolutionise nano-device fabricationFebruary 12th, 2009 - 6:25 pm ICT by IANS
Washington, Feb 12 (IANS) Engineers have created a process that may revolutionise the manufacture of nano-devices from computer memory to biomedical sensors by exploiting a novel type of metal.
The material can be moulded like plastics to create features at the nano-scale and yet is more durable and stronger than silicon or steel. The search for a cost-effective and manageable process for higher-density computer chip production at the nano-scale has been a challenge.
One solution is making nano-scale devices by simple stamping or moulding, like the method used for fabricating CDs or DVDs.
This however requires stamps or master moulds with nano-scale features. While silicon-based moulds produce relatively fine detail, they are not very durable. Metals are stronger, but the grain size of their internal structure does not allow nano-scale details to be imprinted on their surfaces.
Unlike most metals, “amorphous metals” known as bulk metallic glasses (BMGs) do not form crystal structures when they are cooled rapidly after heating.
Although they seem solid, they are more like a very slow-flowing liquid that has no structure beyond the atomic level - making them ideal for moulding fine details, said senior author Jan Schroers of the Yale School of Engineering & Applied Science.
Researchers have been exploring the use of BMGs for about a decade, according to Schroers. “We have finally been able to harness their unusual properties to transform both the process of making moulds and producing imprints,” he said. “This process has the potential to replace several lithographic steps in the production of computer chips.”
Schroers says BMGs have the pliability of plastics at moderately elevated temperatures, but they are stronger and more resilient than steel or metals at normal working temperatures, said an Yale release.
“We now can make template moulds that are far more reliable and lasting than ones made of silicon and are not limited in their detail by the grain size that most metals impose,” said Schroers.
This research was published in Nature on Thursday.
Tags: amorphous metals, atomic level, biomedical sensors, bulk metallic glasses, chip production, computer chips, crystal structures, device fabrication, fine details, grain size, moulds, nano scale, novel type, pliability, scale details, scale features, schroers, science researchers, unusual properties, yale school