Symmetrical bi-heterojunction alternating current ultraviolet light-emitting diode

The development of bidirectional light emitting diodes (LEDs) is significant to avoid stroboscopic effects and save energy for illumination and display applications. However, the existing bidirectional LEDs present different electroluminescent (EL) emission spectra and intensity at forward and reverse bias conditions which causes stroboscopic effects. Herein, A symmetrical bi-heterojunctional n-ZnO/n-GaN/n-ZnO LED was fabricated by bonding n-ZnO microwires on a n-GaN layer. The LEDs generate a stable UV light output under both forward and reverse bias conditions. The EL intensities of LEDs under forward and reverse bias conditions are approximately equal because of symmetrical characters between two heterojunctions. Our results provide a bi-directionbiased bi-heterojunction ultraviolet LED avoiding stroboscopic effects.