Growth of High-Density Zinc Oxide Nanorods on Porous Silicon by Thermal Evaporation

Materials

Nurul Izni Rusli¹  Masahiro Tanikawa²  Mohamad Rusop Mahmood³  Kanji Yasui² 

[1] Faculty of Electrical Engineering, Universiti Teknologi Malaysia, Skudai 81310, Johor, Malaysia; E-Mail:;Department of Electrical Engineering, Nagaoka University of Technology, Kamitomioka-machi, Nagaoka, Niigata 940-2137, Japan; E-Mails:;Faculty of Electrical Engineering, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia; E-Mail:

关键词: zinc oxide;    nanorods;    porous silicon;    thermal evaporation;    vapor-liquid-solid;   

DOI  :  10.3390/ma5122817

来源: mdpi

【 摘 要 】

The formation of high-density zinc oxide (ZnO) nanorods on porous silicon (PS) substrates at growth temperatures of 600–1000 °C by a simple thermal evaporation of zinc (Zn) powder in the presence of oxygen (O₂) gas was systematically investigated. The high-density growth of ZnO nanorods with (0002) orientation over a large area was attributed to the rough surface of PS, which provides appropriate planes to promote deposition of Zn or ZnO_x seeds as nucleation sites for the subsequent growth of ZnO nanorods. The geometrical morphologies of ZnO nanorods are determined by the ZnO_x seed structures, i.e., cluster or layer structures. The flower-like hexagonal-faceted ZnO nanorods grown at 600 °C seem to be generated from the sparsely distributed ZnO_x nanoclusters. Vertically aligned hexagonal-faceted ZnO nanorods grown at 800 °C may be inferred from the formation of dense arrays of ZnO_x clusters. The formation of disordered ZnO nanorods formed at 1000 °C may due to the formation of a ZnO_x seed layer. The growth mechanism involved has been described by a combination of self-catalyzed vapor-liquid-solid (VLS) and vapor-solid (VS) mechanism. The results suggest that for a more precise study on the growth of ZnO nanostructures involving the introduction of seeds, the initial seed structures must be taken into account given their significant effects.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.