A "nano machine shop" that shapes nanowires and ultrathin films could represent a future manufacturing method for tiny structures with potentially revolutionary properties. The new method, called laser shock-induced shaping, makes it possible to tune nanowires by altering electrical and optoelectrical properties that are critical for electronic components.
Researchers at Purdue University in West LaFayette,
Ind., also have shown how laser shock-induced shaping can be used to change the
properties of grapheme - a step toward harnessing the material for electronic
In all, the nano structures may be tuned for applications
ranging from high-speed electronics to solar cells and also may have greater
strength and unusual traits such as ultrahigh magnetism and "plasmonic
resonance," which could lead to improved optics, computers and
The researchers used their technique to stamp nano- and
microgears; form tiny circular shapes out of a material called graphene, an
ultrathin sheet of carbon that holds promise for advanced technologies; and
change the shape of silver nanowires, said Gary Cheng, an associate professor
of industrial engineering at Purdue University.
"We do this shaping at room temperature and
atmospheric pressure, like a nano-machine shop," said Cheng, who is
working with doctoral students Ji Li, Yiliang Liao, Ting-Fung Chung and Sergey
Suslov and physics professor Yong P. Chen.
The technique works by using a multilayered 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
"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
Findings were detailed in research papers published in
the journal Nano Letters.
Nanowires, Ultrathin Films Could Be Manufactured with Laser Heating
August 29, 2012