Optically invariant InGaN nanowire light-emitting diodes on flexible substrates under mechanical manipulation

Abstract

Titled nanowire LED is brighter Nanowire LEDs are more robust than thought in their emission wavelengths, light output when put on flexible substrates, even under mechanical bending. A collaborative team led by Prof William S. Wong from University of Waterloo, Canada demonstrates vertical GaN nanowire LEDs on flexible PET substrates and optimize the light output by tuning the geometric orientation and substrate bending. A facile double-transfer method is developed to migrate the nanowires to a flexible PET substrate while keeping the devices in their original orientation and thus the light output insensitive to substrate bending. More interestingly, the light output can be greatly increased by tilting the GaN nanowires by a small angle from the normal plane, due to enhanced electromagnetic coupling. This work presents a viable way to add the flexibility to nanowire LED devices without compromising the performance.