3D printed nanowalls could improve touchscreens

Touchscreen technology relies on nanowalls of transparent electrodes on the surface of the glass to receive input from our fingers. Until now, these barely visible webs have been fabricated using indium tin oxide, a transparent material with relatively low conductivity. The team at ETH has designed a system that can 3D print nanowalls using gold or silver, which are more conductive and transparent than indium tin oxide, delivering better touchscreen performance.

“Indium tin oxide is used because the material has a relatively high degree of transparency and the production of thin layers has been well researched, but it is only moderately conductive,” said Patrik Rohner, a PhD student at ETH and a member of the research team.

Gold and silver are not naturally transparent, so in order to gain the appearance of transparency, the electrodes are printed between 80 and 500 nanometres thick. To retain the desired levels of conductivity, the nanowalls make use of three dimensions, and the electrodes are created two to four times taller than they are wide.