Flexible and Elastic Electric Circuits (INM Innovation Center)

Knobs, buttons and switches for the operation of electrical equipment are unnecessary in the future. They are replaced by displays on arbitrarily shaped handles that the devices be operated mechanically. Or just any shape surface. This makes possible a development in researchers of the Leibniz Institute for new materials (INM) in Saarbrücken.

The INM scientists have succeeded in to separate electrical circuits on a flexible silicone sheeting. These can be integrated into smooth and curved surfaces and tapping used to operate, and have display capabilities. Be “relatively insensitive to sprains and strains”, say the researchers.

UV light creates traces on the surface

The team of Peter William de Oliveira, in personal Union head of the area of optical materials and the INM Innovation Center, has realized the circuits using a technique called photochemical Metallization. “First we pull over the silicone sheets with a photo-active layer of metal oxide nano particles. Then we have a specially designed liquid containing the colorless silver ions”, so de Oliveira. Irradiation with ultraviolet light they transform into metallic, electrically conductive silver.

Electrical conductor paths only a few micrometers wide

The UV light works not flatly on the slide. It falls rather through a mask, just like in the manufacture of microprocessors and memory chips. Where it hits, such as fine electrical conductors or other structures emerge. These are only a few microns wide, so that they are invisible to the human eye. If it’s not about mass production UV laser, robot controlled on the pre-treated surface write the structures should be inserted.

Flying Butler on Hanover Exhibition
The new flying object named “FreeMotionHandling” from Festo consists of an ultra light carbon ring with eight fully distributed mini-screws. A rotating helium ball, a gripper is mounted at the bottom sits in the middle of the ring. Photo: Festo

Electronics from the printing machine

The films produced so far in the laboratory crafted are just post card size. Together with an industrial partner, the INM researchers still are looking for the production technology to be automated. The silicone film to, are similar to newsprint, continuously coated and irradiated. At the end, the finished electrical circuit is simply rolled up. In this way, already organic light-emitting diodes and solar cells are made from plastic.

The technique works not only on flexible films, but also on glass, such as the, which is used for touch screen smart phones and Tablet PCs. That are microscopic and therefore invisible conductor paths that pass on the touch as control commands. These are manufactured so far in several steps. In the future, one is enough.

Their results and possibilities show the developers on the Hanover fair at stand B46 in Hall 2 in the framework of the research & technology fair from April 25 to 29.