Almost invisible to human detection, feather-light electronic foil technologies are now being hosted on human skin. Such ultra-thin transistors have inspired virtually unbreakable products that can conform to almost any shape, including details as fine as human skin wrinkles. No another step closer to the creation of an actual cyborg, it will no longer be necessary to carry electronic devices as separate units as they will instead be a layer on the skin indistinguishable from skin itself.

Electronic foils will certainly be seen as a revolution from from the hulking, tube-fired electronics or yesteryear, like wood-cabinet, console televisions. Today’s devices, of course, are highly mobile, but not yet extremely mobile, as they remain rigid, visible and, well, tangible. In what will abhor some and delight others, electronics will soon become intimately integrated with – and into – human bodies.

Moving into the mainstream, electronic foil technology is envisioned as wearable, mobile devices but also for biomedical applications. The organic transistors of the foils will be biodegradable and just two micrometers thick, or about 20 percent that of plastic wrap. Electronic foils may also be just as common one day.

Electronic foil sheets are thirty times lighter in weight than standard office paper and can be scrunched tightly without harm to the circuits. Created in huge rolls, they can be manufactured on a large scale and inexpensively. Electronic foils endure harshly dynamic conditions, surviving severe bending and stretching, under water, and at elevated temperatures.

It all started relatively recently when researchers from the University of Illinois at Urbana-Champaign and Northwestern University published the report Stretchable batteries with self-similar serpentine interconnects and integrated wireless recharging systems in 2013, This opened the door for the new generation of flexible electronics. Soon available for use virtually anywhere, stretchable electronics will also be used inside the human body, monitoring heart activity or brain waves.

Breakthrough work came from a team led by Martin Kaltenbrunner at the University of Tokyo. Its goals were super-thin, inexpensive and bendable circuits that could be used over large areas. Using techniques common to today’s semiconductor industry (such as vacuum evaporation and chemical vapor deposition), the team successfully laminated integrated organic circuits onto ultra-thin plastic films, also known as polymer foils.

When unified with a tactile sensor, one possible use of electronic foil would occur on the roof of a person’s mouth. Kaltenbrunner said it “would be a nice interface” for a person that is not able to communicate with anything but their tongue. For those with such communication challenges, yes or no answers could be given by touching different places of the sensor, while more complex articulation could be easily imagined. He says  the technology is “getting really close to what I’ve seen in sci-fi movies, where you just touch a surface and it does something.”

A sensor of this type could add touch sensitivity – used as artificial skin – to new developments in robot technologies. Other possibilities include thin-film heaters, organic solar cells, temperature / infrared sensors and displays and tactile sensors for health care and monitoring.