SYNTHESIS AND PROPERTIES OF Tb-DOPED GaN NANOWIRES

摘要

The synthesis of Tb-doped GaN nanowires on Si (111) substrates through ammoniating Ga_2O_3 films doped with Tb was investigated. X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy and photoluminescence were used to characterize the composition, structure, morphology and optical properties of the products. The results show that the as-synthesized GaN nanowires doped with 3 at. % Tb are of single-crystalline hexagonal wurtzite structure. The nanowires have diameters ranging from 20 to 50 nm and the lengths up to tens of micrometers. An f-f intra-atomic transition of rare earth at 545 nm corresponding to ~5D~4-~7F_5 of the Tb~(3+) and other two peaks related with doping are observed in PL spectrum, confirming the doping of Tb into GaN. The growth mechanism of GaN nanowires was discussed briefly.