Structural evolution of AlN nano-structures: Nanotips and nanorods

Aluminum nitride (AIN) nanostructures were prepared using thermal chemical vapour deposition process. At growth temperatures of 950 degrees C, AIN nanotips with apex diameters of 10 nm, base diameters of similar to 100 nm, and length of similar to 2000 nm were obtained. Whereas when the growth temperature was 1200 degrees C, we obtained shorter and ihicker AIN nanorods. Compelling microscopic evidences were obtained to show that stacked AIN platelets of diminishing size formed the building blocks for the nanotips. A reducing Ehrlich-Schwoebel barrier introduced into a diffusion mediated growth model explains the formation of AIN nanorods at increasing growth temperatures. (c) 2005 Elsevier B.V. All rights reserved.