Preparation of carbon thin films from five-membered heterocyclic organic compounds by chemical vapor deposition

Thin carbon films were prepared from five-membered heterocyclic organic compounds [tetrahydrofuran (THF), borane-THF (B-THF), pyrrolidine (PYL), 1-3 dimethyl-2-imidazolidinone (DMI), cyclopentane (CP)] by chemical vapor deposition (CVD). The vapor generated by heating the compound was carried by flowing Ar and decomposed on a silica glass substrate to deposit carbon films at 750 to 1000 °C. The films were studied by scanning electron microscopy (SEM), X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Their growth rates were determined as a function of temperature (750 to 1000 °C) and Ar flow rate (5 to 35 ml min−1). The presence of pyridine- and pyrrole-type nitrogen was confirmed in the PYL- and DMI-derived carbon films. The electrical conductivity of films prepared at 800 and 900/1000 °C was of the order of 103 and 104 S m−1, respectively. The micro-Vicker's hardness of films prepared at 800 °C was 2.2-3.6 GPa, becoming greater (3.3-5.2 GPa) at 1000 °C.