Section 14. Wide band gap materials. II. Micro/nano carbon structures and nanotubes Carbon nano-structures containing nitrogen and hydrogen prepared by ion beam assisted deposition

In this paper, we report the synthesis and some properties of nano-structured carbon films grown on nanometric nickel particles at 700 � C by ion beam assisted deposition (IBAD). In situ photoelectron emission spectroscopy (XPS) reveals the presence of nitrogen in the carbon layer coating the nickel particles. Atomic force microscopy (AFM) displays regular dome-like structures with a mean width, height, and density of � 170 nm, � 22 nm, and � 1.4 · 10 9 domes/cm 2 , respectively. Raman spectroscopy shows the characteristic frequencies associated with graphite and disordered structures. Disorder increases on increasing nitrogen content. High-resolution transmission electron microscopy (HRTEM) confirms the presence of multiwall well-organized graphite layers covering the nickel particles. The field emission properties of the structures are reported.