Authors: K. Teker, A. Siemann
Affilation: Istanbul Sehir University, Turkey
Pages: 60 - 63
Keywords: photoconductivity, GaN nanowires, photodetectors
Gallium nitride nanostructures continue to attract great interest due to their applications in optoelectronic devices (UV photodetectors, and light-emitting devices), high-power/high temperature electronics, nanosensing, and piezoelectric nanogenerators. This paper presents a systematic photoconductivity investigation of the GaN nanowires. GaN nanowires have been produced by chemical vapor deposition using Ga and NH3 as source materials on SiO2/Si substrate at 1100oC under H2 as carrier gas. Nanowire FET devices have been fabricated. A unique annealing scheme has been implemented to improve contacts between nanowires and gold electrodes, which resulted in very consistent electrical measurements. Photoconductivity studies of the AlN nanowires have been conducted at various light sources with wavelengths of 254 nm, 365 nm, 532 nm and 633 nm using a semiconductor parameter analyzer. Significant positive photocurrent responses have been measured under different photon energy excitations. Furthermore, photocurrent decay has been very rapid after the illumination ended. These studies will provide crucial information and insights for the development of UV optoelectronic devices and light sensors. The grown nanowires and devices have been characterized by SEM, XRD, TEM, FTIR, and semiconductor parameter analyzer.