Growth of single-crystalline wurtzite aluminum nitride nanotips with a self-selective apex angle
Journal
Advanced Functional Materials
Journal Volume
15
Journal Issue
5
Pages
781-786
Date Issued
2005
Author(s)
Abstract
Single-crystalline, hexagonal aluminum nitride nanotips are fabricated using a vapor-transport and condensation process (VTCP) on silicon substrates with or without a catalyst layer. The resultant tips have very sharp nanoscale apexes (∼1 nm), while their bases and lengths are up to hundreds of nanometers wide and several micrometers long, respectively. It has been demonstrated that the thickness of the gold-catalyst layer plays a critical role in controlling the size of the tip; in addition, a catalyst-free growth mode has been observed, which results in lesser control over the nanotip morphology. Nevertheless, a remarkably narrow distribution of the apex angle of the nanotips, regardless of whether or not a catalyst was used in the VTCP, has been obtained. Compared with the commonly observed ridge and pyramid structures, the nanotips produced by VTCP have higher angles (∼81°) between the tilted (221) and the basal (001) planes that encase it. A mechanism for this self-selective apex angle in aluminum nitride nanotip growth is proposed. © 2005 WILEY-VCH Verlag GmbH KGaA, KGaA, Weinheim.
SDGs
Other Subjects
Catalysts;Condensation;Crystal growth;Fabrication;Gold;Nanostructured materials;Scanning electron microscopy;Silicon compounds;Single crystals;Transmission electron microscopy;Vaporization;X ray diffraction analysis;Apex angles;Nanometers;Nanorods;Nanotips;Aluminum nitride
Type
journal article