Preparation And Characterization Of InN Nanowires And Nano-tubes

InN has the smallest effective electron mass among all theⅢ-nitride, which leads to high mobility, high saturation velocity, and a large drift velocity at room temperature. So InN is regarded as a promising material and has been extensively investigated in solid-state lighting, photovoltaics, terahertz emitter and detectors.Low dimensional semiconductor of InN attracted a lot of interests for its novel properties because of quantum confinement effect.In this work, on dimensional InN nano-structures were synthesized by two-step growing method, via a vapor-solid growth mechanism of nitriding indium oxide(In2O3) in ammonia flux. The reaction was carried out via two steps:(1)In2O3 powers was thermally nitrided in ammonia flux at the temperature of 600℃for 4 hours, and we got sample 1;(2)sample 1 was annealed at 650℃in the atmosphere of NH3 for 2 hours, then we got sample 2. The color of the sample changed from dark to brown after the treatment of step 2. And the morphology of sample 1 changed after the process of annealing from nanoparticles to nanowires and nanotubes, observed by transmission electron microscopy (SEM) and scanning electron microscopy (TEM). Infrared photoluminescence (IR-PL), energy diffraction spectroscopy (EDS), infrared reflectance spectrum(IR-RS) and X-ray diffraction(XRD) methods were used here to investigate the characters of these two samples. And the mechanism of the two-step growth was also discussed.