Synthesis and field emission properties of aluminum nitride nanocones Chun Liu a , Zheng Hu a, * , Qiang Wu a , Xizhang Wang a , Yi Chen a , Weiwei Lin b , Hai Sang b , Shaozhi Deng c , Ningsheng Xu c a Key Laboratory of Mesoscopic Chemistry of MOE and Jiangsu Provincial Lab for NanoTechnology, Department of Chemistry, Nanjing University, Nanjing 210093, China b National Laboratory of Solid State of Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China c State Key Laboratory for Optical and Electric Materials and Technology, Zhongshan University, Guangzhou 510275, China Available online 26 April 2005 Abstract One-dimensional aluminum nitride nanostructures have displayed superior field emission due to the combination of small or negative electron affinity and one-dimensional quantum confinement effect. Herein we report on the synthesis of quasi-aligned AlN nanocones via chemical vapor deposition on the Ni-coated silicon wafer at 750 8C through the reaction between AlCl 3 vapor and NH 3 /N 2 gas. The as-prepared hexagonal AlN nanocones grow preferentially along c-axis with the tips’ sizes of about 60 nm and the lengths up to several microns. The field emission measurement exhibits a notable electron emission with the apparent turn-on field of 17.8 V/mm, indicating their potential applications as the field emitters. Due to space charge effect, the corresponding Fowler–Nordheim plot shows a two-sectional characteristic with the field enhancement factors of 1450 and 340 at low and high electric fields, respectively. # 2005 Elsevier B.V. All rights reserved. PACS: 79.70.+q Keywords: AlN nanocones; Chemical vapor deposition; Field emission; Two-sectional Fowler–Nordheim plot; Space charge effect 1. Introduction Carbon nanotubes (CNT), a novel form of carbon discovered in 1991, have been widely recognized as one of the most promising field electron emitters due to their excellent electrical properties and one- dimensional (1D) geometry. Their applications in the fields such as flat panel displays, microwave power amplifier tubes as well as electron guns in scanning electron microscope and transmission electron micro- scope have been fully developed [1,2]. Stimulated by the success of CNTs, 1D nanostructures of other materials have also been explored for their potential as field emitters. Among them, 1D AlN nanostructures www.elsevier.com/locate/apsusc Applied Surface Science 251 (2005) 220–224 * Corresponding author. Tel.: +86 25 83686015; fax: +86 25 83686251. E-mail address: zhenghu@nju.edu.cn (Z. Hu). 0169-4332/$ – see front matter # 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.apsusc.2005.03.101