Computer components could be damaged during manufacturing if irradiation is used to manipulate properties of small-scale materials, researchers from the University of Huddersfield have found.
The team led by Professor Stephen Donelly, has studied effects of irradiation on nanomaterial properties. During the experiment they irradiated gold nanorods with a beam of xenon atoms and observed the changing properties of the material.
“We were hoping to generate bubbles but we actually found that we were eroding the nanowires,” said Graeme Greaves, one of the authors of the study recently published in the journal Physical Letters Review.
“The sputtering yield of a normal piece of flat gold should be of the order of 50 atoms per ion,” Greaves said, explaining that sputtering yield measures how many atoms come out of the matter for each incoming atom
“In the case of rods we expected it to be greater, because the geometry is much reduced. We worked out that it should be higher by a factor of four, or something of that order. But we actually found that the greatest value measured was a sputtering yield of a thousand – a factor of 20.”
The findings are bad news for computer component manufacturers who frequently use ion beams to modify properties of small-scale materials used in chips.
The results of the study were verified independently by researchers from the University of Helsinky, Finland, who run a molecular dynamics simulation, creating a virtual gold nanorod. Their conclusions confirmed those of the Huddersfield team.
Apart from computer components manufacturing, the research has considerable implications for medicine, Greaves believes.
“More and more people are working on nanostructures for practical applications. Gold nanoparticles can be used for tumour detection, the optimisation of the bio-distribution of drugs to diseased organs and a radiotherapy dose enhancer,” he said.