Fabrication and Characterization of Alternating-Current-Driven ZnO-Based Ultraviolet Light-Emitting Diodes

Alternating-current-driven ZnO-based light-emitting diodes (LEDs) with an Au/ZnMgO/ZnO/ZnMgO/GaN/In structure have been fabricated. Both polarity-controlled electroluminescence (EL) and ultraviolet emission were achieved when driven by an alternating current (AC) under a much lower root-mean-square voltage than that of conventional inorganic AC thin-film electroluminescent devices. This ZnO-based LED can be regarded as a series incorporating a metal-insulator-semiconductor diode and a p-i-n diode. The EL mechanisms were discussed in terms of the band diagrams and carrier transport behavior with reference to the semiconductor heterojunction theory. Open image in new window