화학공학소재연구정보센터
Thin Solid Films, Vol.377-378, 163-169, 2000
Morphology of crystalline nitrogenated carbon films prepared by HF-CVD
A hot filament chemical vapour deposition (HF-CVD) process has been used for fabrication of crystalline nitrogenated carbon (C:N) films without hydrogen additions. Decomposition of methane (CH4) in nitrogen (N-2) atmosphere results in a new type of him growth characterised by various polymorphs including worm- or needle-like microstructures. Therefore these films show a large surface area. Under certain deposition conditions thigh filament and substrate temperature, small distance, r, between filament and substrate) very high deposition rates up to 2000 nm/min were achieved and the formation of a cauliflower structure was observed. Additionally coiled carbon fibres and chains of nanobeads were produced which shape, diameter and length depend on the lateral distance from the filament. These tubular structures show an interesting feathered surface. The structure and the chemical composition of the deposited C:N films were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron energy loss spectroscopy (EELS). The crystallinity of the films is derived from the lattice planes clearly seen in high resolution (HR) TEM. By Raman spectroscopy the vibrational properties were observed showing a disordered graphitic-like structure.