Fabrication of zinc oxide nanostructures on gold-coated silicon substrate by thermal chemical reactions vapor transport deposition in air

The aim of this work was to carry out systematic studies of how synthesis temperatures affect the morphology and properties of mixed zinc sulfide/zinc oxide (ZnSxOy and ZnO) nanostructures, and to get reliable data on optical constants of ZnSxOy and ZnO nanowires/nanobelts (NW/NB) for the use in device applications. ZnSxOy and ZnO NWs/NBs were fabricated using vapor transport in an open-end tube. Mixed ZnS0.47O0.62NWs was obtained at the synthesis temperature of 850 °C. The sulfur content disappeared as the temperature increased to 950 °C and 1050 °C and the morphology changed to a mixture of NW/NB. The NW prepared at 850 °C were indexed as mixed phases of hexagonal ZnS and hexagonal ZnO structures. The NW/NB prepared at 950 °C and 1050 °C were indexed as pure hexagonal ZnO structures. The thickness, surface roughness, and optical constants of the synthesized nanostructured samples were extracted from measurements of spectroscopic ellipsometry. A two-layers model was proposed to fit the calculated data to the measured ellipsometric spectra. The estimated band gap values of the prepared nanostructures lay 0.66–0.79 eV below the bulk ZnO value due to the lower oxygen content present in the samples and the stresses built in the samples during preparation.

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Characterization of Urea versus HMTA in the Preparation of Zinc Oxide Nanostructures by Solution-Immersion Method Grown on Gold-Seeded Silicon Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.364.45 ◽

2011 ◽

Vol 364 ◽

pp. 45-49 ◽

Cited By ~ 9

Author(s):

Azlinda Ab Azlinda ◽

Zuraida Khusaimi ◽

Saifollah Abdullah ◽

Mohamad Rusop

Keyword(s):

Zinc Oxide ◽

Silicon Substrate ◽

High Surface ◽

High Surface Area ◽

Zinc Nitrate ◽

Nitrate Hexahydrate ◽

Zno Nanostructures ◽

Zinc Oxide Nanostructures ◽

Immersion Method ◽

Oxide Nanostructures

Zinc oxide (ZnO) nanostructures prepared by immersion method were successfully grown on gold-seeded silicon substrate using Zinc nitrate hexahydrate (Zn (NO3)2.6H2O) as a precursor, separately stabilized with non-toxic urea (CH4N2O) and hexamethylene tetraamine (HMTA). The effect of changing the stabilizer of ZnO solution on the crystal structure, morphology and photoluminescence properties of the resultant ZnO is investigated. X-ray diffraction of the synthesized ZnO shows hexagonal zincite structure. The morphology of the ZnO was characterized using Field Emission Scanning Electron Microscope (FESEM). The growth of ZnO using urea as stabilizer shows clusters of ZnO nanoflower with serrated broad petals were interestingly formed. ZnO in HMTA showed growth of nanorods. The structures has high surface area, is a potential metal oxide nanostructures to be develop for optoelectronic devices and chemical sensors. The formation of ZnO nanostructures is found to be significantly affected by the stabilizer.

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