Printing Silicon On Paper, With Lasers

Picture source: http://www.kurzweilai.net/
INDUSTRIAL ENGINEER – VOLUME 47, NUMBER 6

Fabrication technique cuts out inhibiting, high-temperature process
Researchers at Delft University of Technology have pioneered a method that allows the polycrystalline form of silicon used in circuitry to be produced directly on a substrate from liquid silicon ink with a single laser pulse.

Obviously, wearable electronics are the most immediate application of printing fast, low-power and flexible transistors at a remarkably low cost, said professor Ryoichi Ishihara, who led the research team, which collaborated with the Japan Advanced Institute of Science and Technology. But he envisions expanding the process to biomedical sensor and solar-cell areas, along with stretchable “and even edible” electronics.

Previously, the ability to print silicon ink onto substrates required a thermal annealing step at 350 degrees Celsius, far too hot for many of the flexible surfaces that made production appealing in the first place. The new method bypasses this step, transforming the liquid silicon directly into polysilicon. They detailed their research in Applied Physics Letters from AIP Publishing.