Well-aligned ZnO microprism arrays with umbrella-like tips: Low-temperature preparation, structure and UV photoluminescence improvement

State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Changning Road, Shanghai 200050, People's Republic of China
Physica E Low-dimensional Systems and Nanostructures (Impact Factor: 1.86). 08/2008; 40(9):2931-2936. DOI: 10.1016/j.physe.2008.02.012

ABSTRACT Catalyst-free, low-temperature (430 °C), high-density, well-aligned, single-crystalline zinc oxide (ZnO) microprism (ZMP) arrays have been synthesized over the entire c-ZnO/poly-Zn-coated Si substrates by simple thermal evaporation of Zn powder. Specially, the microprisms obtained possess hexagonal umbrella-like tips on which vertical thin ZnO nanowires grow. The growth mechanism of a three-stage thermodynamic process was discussed. Photoluminescence spectra show a strong ultraviolet (UV) emission enhancement of the ZMPs after H+ (hydrogen ions) implantation. This kind of special ZnO microstructure may find potential applications in field emission, UV laser emission devices, multifunctional microdevices and highly integrated multichannel nano-optoelectronic devices.

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