Study on the Fabrication of Uv Led Based on Au/I-Aln/N-Gan Structure and the Effect of Operating Temperature on the Carrier Transmission and Electroluminescence Characteristics

Abstract

In this paper, a series of MIS (metal-insulator-semiconductor) type diodes with Au/i-AlN/n-GaN structure were prepared by varying the deposition time of AlN thin films, and the influence of the ambient temperature on the current-voltage (I-V) and electroluminescence (EL) properties were investigated. I-V tests showed that the appropriate deposition time can reduce the turn-on voltage and leakage current of the device, and the device displayed excellent rectification behavior at different ambient temperatures (30-70℃). In addition, EL spectra showed that the Au/i-AlN/n-GaN diode exhibited high-purity ultraviole (UV) emission (374 nm) when the deposition time was 40 minutes. The ultraviolet electroluminescence intensity of the device first increased and then decreased with increasing ambient temperature, which may be attributed to the formation of extra non-radiating recombination centers in the heterojunction due to the high temperature. Finally, we clarified the source of holes from the energy band structure and discussed the luminescence mechanism of the device.

Keywords: AlN films, Deposition time, Metal-Insulator-Semiconductor structure, Operating temperature