Ultrathin quantum dot LED that can be folded freely as paper

Quantum dot light-emitting diode (QLED), which employs quantum dots arsenic a light-emitting material, has attracted important attraction arsenic a promising alternate for next-generation show technologies, owing to its outstanding electroluminescence properties. Since it does not necessitate immoderate bulky components specified arsenic backlight units, QLED displays tin perchance beryllium manufactured into an ultrathin signifier factor. A associated probe squad led by KIM Dae-Hyeong (Professor astatine Seoul National University) and HYEON Taeghwan (Distinguished prof astatine Seoul National University) from the Center for Nanoparticle Research wrong the Institute for Basic Science has antecedently unveiled a prototype QLED backmost successful 2015. The instrumentality had a thickness of lone 3 micrometers, which is lone one-thirtieth of that of quality hair. Due to specified an highly reduced thickness, the ultrathin QLED exhibited outstanding mechanical flexibility, which allowed it to beryllium readily applicable successful assorted wearable devices, specified arsenic physics tattoos.

Recently, the squad further precocious this exertion and developed a foldable variant of the ultrathin QLED, inspired by the past creation of insubstantial folding known arsenic origami. The IBS researchers reported three-dimensional foldable QLEDs, which tin beryllium freely transformed into assorted user-customized 3D structures, specified arsenic butterflies, airplanes, and pyramids. Considering the rising popularity of foldable smartphones, the advancement of foldable show exertion is gaining greater importance. It is expected this exertion tin supply unprecedented opportunities for next-generation electronics with user-customized signifier factors with analyzable structures, arsenic good arsenic allowing for dynamic three-dimensional show of ocular information.

The researchers endowed foldability to the accepted planar QLED via a caller fabrication process that tin partially etch the epoxy movie deposited connected the QLED aboveground without damaging the underlying QLED. Using a power-controllable c dioxide pulsed laser and the silver-aluminum alloy-based etch-stop layers, the etching extent tin beryllium precisely controlled. As the laser-etched portion of the instrumentality is comparatively thinner than the surrounding region, it is imaginable to etch retired deformation lines on which the instrumentality tin beryllium folded similar origami paper.

Video 1. Foldable QLEDs with assorted shapes specified arsenic airplanes, butterflies, and pyramids. Credit: Institute for Basic Science

Based connected the selective laser-etching technique, researchers were capable to precisely power the radius of curvature down to little than 50 micrometers. Under specified a tiny curvature radius, the fold enactment resembles a crisp borderline with nary disposable curvature. By utilizing mechanical simulation to cautiously technologist the device, researchers were capable to minimize the strain loaded connected the light-emitting components. The full QLED including the crease portion (a fold line) was capable to support a unchangeable light-emitting show adjacent erstwhile aft it was repeatedly folded 500 times. The exertion was applied to fabricate 3D foldable QLEDs with assorted analyzable shapes specified arsenic butterflies, airplanes, and pyramids.

"We were capable to physique a 3D foldable QLED that tin beryllium freely folded conscionable similar a insubstantial artwork," said KIM Dae-Hyeong, the vice-director of the Center for Nanoparticle Research. He besides said, "By fabricating the passively driven, 3D foldable QLED arrays composed of 64 idiosyncratic pixels, we person shown the anticipation of processing displays with greater complexity successful the future." HYEON Taeghwan, the manager of the Center for Nanoparticle Research, states that "Through the technology reported successful this research, paper-like QLEDs that tin beryllium folded into assorted analyzable structures person been successfully fabricated. Who knows erstwhile the time volition travel erstwhile physics insubstantial with a display portion tin regenerate existent paper?"

---

---