Printed electronics have evolved significantly over the last years, with researchers creating new flat and flexible designs for electronic components, such as circuits, for the electronic-device form factors of the future.
Ultra-thin and ultra-flexible electronic material developed by research led by scientists at RMIT University could be printed and rolled out like newspaper for the development of future touchscreen technology. (Image source: RMIT University)
Now a team at RMIT University has created an ultra-thin and highly flexible material that can be printed and rolled out like newspaper. The researchers—who collaborated with other scientists at the University of New South Wales, Monash University and the ARC Centre of Excellence in Future Low-Energy Electronics Technologies—believe the material can be used to develop future touchscreen technologies.
“You can bend it, you can twist it, and you could make it far more cheaply and efficiently than the slow and expensive way that we currently manufacture touchscreens,” said lead researcher Torben Daeneke, an Australian Research Council fellow at RMIT.
Previously, most mobile phone touchscreens were made of a transparent material, indium-tin oxide (ITO), which is highly conductive but also quite brittle. Daeneke’s team has repurposed this material using a liquid metal chemistry to shrink it from 3D to 2D, a process that also added a capacity for the material to bend, he said. “We’ve taken an old material and transformed it from the inside to create a new version that’s supremely thin and flexible,” said Daeneke.
To create the new atomically-thin ITO used in the novel material, the researchers heated an indium-tin alloy to 200 Celsius; at this temperature, it becomes a liquid. Then they rolled the material over a surface to print off nano-thin sheets of indium tin oxide.
These 2D nano-sheets have the same chemical composition as standard ITO but a different crystal structure, which gives them new mechanical and optical properties that researchers found well-suited to their work.
In addition to being fully flexible, the new type of ITO absorbs just 0.7 percent of light, compared with the 5 percent to 10 percent of standard conductive glass. If scientists want to make it more electronically conductive, they can just add layers to the material.
The ultimate result is a new touch-responsive technology that’s 100 times thinner than existing touchscreen materials and so pliable it can be rolled up like a tube for potential manufacturing through the same type of roll-to-roll (R2R) processing used to print newspapers.
Transparency Saves Energy
The added benefit of allowing more light to pass through and thus becoming more transparent means touchscreens being made from the material would require less electrical energy, Daeneke noted. “This means a mobile phone with a touchscreen made of our material would use less power, extending the battery life by roughly 10.”
Researchers published a paper on their work in the journal Nature Electronics.
They’ve already used the new material to create a working touchscreen as a proof-of-concept, and also applied for a patent for the technology. In addition to touchscreens, other optoelectronic applications for the material include LEDs and touch displays, as well future solar cells and smart windows.
Elizabeth Montalbano is a freelance writer who has written about technology and culture for more than 20 years. She has lived and worked as a professional journalist in Phoenix, San Francisco and New York City. In her free time she enjoys surfing, traveling, music, yoga and cooking. She currently resides in a village on the southwest coast of Portugal.