N-ZNO/N-GAN/N-ZNO HETEROJUNCTION-BASED BIDIRECTIONAL ULTRAVIOLET LIGHT-EMITTING DIODE AND PREPARATION METHOD THEREFOR

摘要

An N-ZnO/N-GaN/N-ZnO heterojunction-based bidirectional ultraviolet light-emitting diode and a preparation method therefor. The diode comprises: N-ZnO microwires (1), an N-type GaN film (2), a PMMA protective layer (3), and alloy electrodes (4). The preparation method comprises the following steps: laying two N-ZnO microwires (1) on the N-GaN thin film (2), forming the PMMA protective layer (3) by spin coating to fix the N-ZnO microwires (1) until the PMMA protective layer (3) covers the N-ZnO microwires, solidifying the PMMA protective layer (3) on a drying table, etching the PMMA protective layer (3) using O₂ until the N-ZnO microwires (1) are exposed, and respectively preparing alloy electrodes (4) on different N-ZnO microwires (1) to create N-ZnO/N-GaN/N-ZnO heterojunctions so as to form a complete device. An N/N/N symmetric structure is created, and the total amount of light emitted by the device in both forward and reverse directions is the same. The device is composed of N-type ZnO and N-type GaN. The light-emitting position of the device is in an ultraviolet area. The turn-on voltage of the device is small. The light-emitting center of N-ZnO/N-GaN/N-ZnO heterojunction-based light-emitting diode is at 371 nm and 385 nm, and the ultraviolet luminescence accounts for more than 80%. The device can work normally under the drive of an alternating current.