LEDs Can Now be Printed on Paper

The rate at which applications are developing every day, even the most impossible concept can be made real.  One such advancement in the making is the LED array that can be printed on a sheet of paper.

A thesis done by Gul amin who recently received his doctorate at the Physical Electronics and Nanotechnology group, Campus Norrokoping, showed how it is possible to grow white LEDs directly on paper and also print them on wallpaper.

These white LEDs that are made from a conducting polymer and zinc oxide (ZnO) can be produced directly on a paper. Patent is pending for this method. First the paper has to be coated with a thin water repellent, protective and levelling layer of cyclotene, a resin.

Professor Magnus Willander, who is leading the research said, "This is the first time anyone has been able to build electronic and photonic inorganic semiconducting components directly on paper using chemical methods."

This study was published in Wiley's Phys. Status Solidi -- Rapid Research Letters.

Gul also showed how it is possible to grow nanorods on paper, blow them off the surface using ultrasound and collect them in the form of powder. This powder can then be used to print the nanorods of zinc oxide, and thus LEDs, on paper or plastic in a normal printing press.