'Nano machine shop' research shapes nanowires

'Nano machine shop' research shapes nanowires

MANHASSET, NY – Researchers have come up with a future manufacturing method for tiny structures with potentially revolutionary properties.

A "nano machine shop" shapes nanowires and ultrathin films and these structures might be tuned for applications ranging from high-speed electronics to solar cells.

It also may have greater strength and unusual traits such as ultrahigh magnetism and "plasmonic resonance," which could lead to improved optics, computers and electronics, according to the Purdue University researchers.

The researchers used their technique to stamp nano- and microgears; form tiny circular shapes out of graphene. "We do this shaping at room temperature and atmospheric pressure, like a nano-machine shop," said Gary Cheng, associate professor of industrial engineering at Purdue.

The laser shock-induced shaping method makes it possible to tune nanowires by altering electrical and optoelectrical properties that are critical for electronic components.

The researchers also have shown how laser shock-induced shaping can be used to change the properties of graphene, a step toward harnessing the material for electronic applications.

The technique works by using a multi-layered sandwich structure that has a tiny mold at the bottom.

Nanowires were situated directly above the mold, and other materials were layered between the nanowires and a glass cover sheet. Exposing this layered "forming unit" to an ultra-fast pulsing laser causes one of the layers to burn up, generating a downward pressure that forces the nanowires into the mold and changes their shape.

"The process could be scaled up for an industrial roll-to-roll manufacturing process by changing laser beam size and scanning speed," Cheng said. "The laser shock-induced shaping approach is fast and low-cost."

Findings were detailed the journal Nature Photonics.

Part of the research, funded by the National Science Foundation, was carried out in a specialized clean room at the Birck Nanotechnology Center in Purdue's Discovery Park.
TAG:Research Nanowires