The authors gratefully acknowledge the financial supports for this project from the National Science Council (NSC) and the Ministry of Education (MOE) in Taiwan. The authors also thank Prof. Guang-Yu Guo and Chung-Huai Chang in the Department of Physics, National Taiwan University, for technical support.
Growth of Single-Crystalline Wurtzite Aluminum Nitride Nanotips with a Self-Selective Apex Angle†
Article first published online: 26 APR 2005
Copyright © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 15, Issue 5, pages 781–786, May, 2005
How to Cite
Shi, S. C., Chen, C. F., Chattopadhyay, S., Lan, Z. H., Chen, K. H. and Chen, L. C. (2005), Growth of Single-Crystalline Wurtzite Aluminum Nitride Nanotips with a Self-Selective Apex Angle. Adv. Funct. Mater., 15: 781–786. doi: 10.1002/adfm.200400324
- Issue published online: 26 APR 2005
- Article first published online: 26 APR 2005
- Manuscript Accepted: 3 DEC 2004
- Manuscript Received: 19 JUL 2004
- Aluminium nitride;
- Nanostructures, inorganic
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.