CVD Synthesis of Graphitic Carbon Nitride Films from Melamine

Abstract

A CVD technique has been developed for the deposition of homogeneous graphitic carbon nitride films on silicon and quartz glass substrates using melamine as a precursor. Layer-by-layer deposition at low precursor loadings makes it possible to deposit a film up to 1.4 µm thick; however, it is possible to achieve large thicknesses by multiple repetition of the experimental cycle. The effect of synthesis parameters on the surface morphology of deposited layers has been studied by scanning electron microscopy. The chemical composition and structure of graphitic carbon nitride films are confirmed by a set of spectroscopic methods and X-ray diffraction. The optical properties have been studied using diffuse reflectance spectroscopy. Scanning electron microscopy and X-ray diffraction analysis have shown that films deposited at temperatures of 550–650°C have a layered microcrystalline structure. The bandgap of the obtained samples was 2.76–2.93 eV.