Washington: New study by a team of scientists has resulted in the development of a diamond-like carbon material that doesn’t wear.
The study was carried out by researchers at the University of Pennsylvania, the University of Wisconsin-Madison and IBM Research-Zurich.
They fabricated an ultra sharp, diamond-like carbon tip possessing such high strength that it is 3,000 times more wear-resistant at the nanoscale than silicon.
This resulted in a diamond-like carbon material mass-produced at the nanoscale that doesn’t wear.
According to researchers, the new nano-sized tip wears away at the rate of one atom per micrometer of sliding on a substrate of silicon dioxide, much lower than that for a silicon oxide tip which represents the current state-of-the-art.
Consisting of carbon, hydrogen, silicon and oxygen molded into the shape of a nano-sized tip and integrated on the end of a silicon microcantilever for use in atomic force microscopy, the material has technological implications for atomic imaging, probe-based data storage and as emerging applications such as nanolithography, nanometrology and nanomanufacturing.
The importance of the discovery lies not just in its size and resistance to wear but also in the hard substrate against which it was shown to perform well when in sliding contact: silicon dioxide.
Because silicon – used in almost all integrated circuit devices – oxidizes in atmosphere forming a thin layer of its oxide, this system is the most relevant for nanolithography, nanometrology and nanomanufacturing applications.
Understanding friction and wear at the nanoscale is important for many applications that involve nanoscale components sliding on a surface.
“It is not clear that materials that are wear-resistant at the macroscale exhibit the same property at the nanoscale,” according to lead author Harish Bhaskaran, who was a postdoctoral research at IBM during the study.
Defects, cracks and other phenomena that influence material strength and wear at macroscopic scales are less important at the nanoscale, which is why nanowires can, for example, show higher strengths than bulk samples.
First Published: Friday, February 26, 2010, 17:04