Sheets of semiconducting oxide just a couple of atoms thick look set to revolutionise the electronics industry after researchers perfected a manufacturing process that works in real world conditions.
A team led by Kourosh Kalantar-zadeh, from the School of Engineering at the Royal Melbourne Institute of Technology in Australia, has developed a new technique that uses liquid metals to create ultra-thin integrated circuits. The results have been published in Nature Communications.
Although various methods of nano-printing have been successful in laboratory situations, they either require very high temperatures to operate, or defeat attempts to scale them up beyond proof of concept.
The key to the team’s success lies in using the metals gallium and indium. Both have low melting points – 30 °C and 156 °C respectively – so they don’t require specialist apparatus in order to be liquidised. When melted, they produce an atom-thin surface layer of oxide, and it is this that the researchers have been able to transfer onto a new substrate, creating an “electronic wafer”.
The wafers are just 1.5 nanometres thick, or 66,666 times thinner than a piece of paper.
The manufacturing process is scalable, so can be adapted to the production of computer chips – which are big things compared to nano-scale objects.
Kalantar-zadeh says the invention will dramatically change the capabilities of electronic devices. Computers and smartphones, he notes, have gained little in processing power in the past half-decade because their circuits have reached the limits of complexity under current manufacturing protocols.
“That is why this new 2D printing technique is so important – creating many layers of incredibly thin electronic chips on the same surface dramatically increases processing power and reduces costs,” he says.
“It will allow for the next revolution in electronics.”