Low-dimensional SiC nanostructures: Fabrication, luminescence, and electrical properties

Nanostructured silicon carbide has unique properties that make it useful in microelectronics, optoelectronics, and biomedical engineering. In this paper, the fabrication methods as well as optical and electrical characteristics of silicon carbide nanocrystals, nanowires, nanotubes, and nanosized films are reviewed. Silicon carbide nanocrystals are generally produced using two techniques, electrochemical etching of bulk materials to form porous SiC or embedding SiC crystallites in a matrix such as Si. Luminescence from SiC crystallites prepared by these two methods is generally believed to stem from surface or defect states. Stable colloidal 3C-SiC nanocrystals which exhibit intense visible photoluminescence arising from the quantum confinement effects have recently be produced. The field electron emission and photoluminescence characteristics of silicon carbide nanostructures as well as theoretical studies of the structural and electronic properties of the materials are described. (C) 2006 Elsevier Ltd. All rights reserved.