In this study, catalytic assisted chemical vapor deposition (CVD) method is applied in the synthesis of III-nitride Core-Shell Nano-materials on direct reactions of ammonia and source materials at elevated temperaures. By using nickel as metal catalyst, hexagonal wurtzite structure of GaN nanowires were successfully obtained on silicon substrate. The produced GaN nanowire was in turn placed in the CVD system and covered by a layer of A1N to synthesize a one-dimensional GaN/A1N core-shell structure. The surface morphology and structure of nanowires is investigated by SEM and TEM. EDS and XRD are used to analyze its composition and lattice structure. Optical properties of GaN/A1N core-shell nanowires are inspected by PL. Our result indicate we successfully synthesize high quality GaN/A1N nanowires and the GaN/A1N nanowires are isgnificantly thicker than the GaN nanowires before coation and the uniform diameter of GaN/A1N nanowires is about four times the value of GaN nanowires which is about 200nm. The TEM and XRD image suggest this material is single crystalline hexagonal wurtzite structure. Form PL Spectrum, we find when the thickness ratio increases from 0 to 2.21, the radiation is changing from GaN reaiation and finally become A1N radiation dominated. The GaN/A1N material can modulate band gap between GaN 3.4eV and A1N 6.2eV, the range of optical performance is blue light to ultraviolet radiation. This result suggested that the scalable processes to synthesis III-nitride nanowires for potential novel solid-state lighting and photonic nano device applications can be acieved.
關聯:
2012 1st International Conference on Material Chemistry: Theoretical, Cpmputationa and Experimental Perspectives p.52
