A handful of iPhone 6 owners were dismayed this past fall to find that their new gadgets bent ever so slightly. Apple responded by stating that the issue was extremely rare and that the products met high endurance standards. Still, some technology companies do want electronics that can bend—on purpose.
Materials scientists have been working on components that can flex and roll for years. In a paper published in September in the journal APL Materials, researchers at Seoul National University describe a recent success for displays: flexible LEDs that could help replace shatter-prone screens. The scientists first grew carpets of microscopic wires of gallium nitride, a light-emitting crystalline material, on an ultrathin mesh of graphene, which is a layer of carbon atoms that is flexible, conductive and tough. They then peeled the graphene-LED sheets off a copper backing and placed them on a pliable polymer—the beginnings of a bendy screen.
The blue LEDs found inside most of today's LCDs—and whose inventors were awarded the Nobel Prize in Physics this year—use gallium nitride because it is energy efficient and bright. It has been difficult to grow the material on a pliable surface, however. The Korean team's new LEDs, which can shine without interruption through more than 1,000 bending cycles, seem to balance the trade-off between quality and flexibility. If the researchers can integrate these individual sheets to make a full display, the LEDs might be found in future phones that bend—by design.