Liquid metal nano-printing for atom-thick ICs

1 min read

A technique using liquid metals to create atoms-thick integrated circuits could lead to the next big advance for electronics, say researchers at RMIT University, Melbourne.

The team, working with the CSIRO, Monash University, North Carolina State University and the University of California, claims the process opens the way for the production of large wafers 1.5nm thick.

"The fundamental technology of car engines has not progressed since 1920 and the same is happening to electronics. Mobile phones and computers are no more powerful than five years ago,” said Professor Kourosh Kalantar-zadeh, from the RMIT School of Engineering.

"That is why this new 2D printing technique is so important – creating many layers of thin electronic chips on the same surface increases processing power and reduces costs."

According to the researchers, the wafers could overcome the limitations of current chip production and could also improve flexible materials.

“Our solution is to use gallium and indium, which have a low melting point,” explained Benjamin Carey, a researcher with RMIT and the CSIRO. “These metals produce an atomically thin layer of oxide on their surface that naturally protects them. It is this thin oxide which we use in our fabrication method.”

"By rolling the liquid metal, the oxide layer can be transferred on to a wafer, which is then sulphurised. The surface of the wafer can be pre-treated to form individual transistors.

“We have used this novel method to create transistors and photo-detectors of very high gain and very high fabrication reliability in large scale."