Low-Voltage UV-Electroluminescence from ZnO-Nanowire Array/p-GaN Light-Emitting Diodes

UV LEDs: The fabrication of an ITO/ZnO-nanowires/p-GaN/In-Ga LED structure is reported with an active emitting layer made of high-quality epitaxial ZnO grown electrochemically from a solution at low temperature (85 degrees C). A narrow ultra-violet electroluminescence centered at 397 nm is obtained at room temperature starting at an applied forward bias of 4.4 V (see figure). The emission is of high brightness and stable at low applied voltages beyond 6 V.