Characterization of carbon nitride thin films deposited by microwave plasma chemical vapor deposition

The carbon nitride films have been prepared on Si substrates using microwav e plasma chemical vapor deposition (MPCVD) technique. The experimental X-ra y diffraction (XRD) spectra of films deposited on Si substrates appear to c ontain all of the strong peaks of alpha-C3N4 and beta-C3N4, but there is co nsiderable peak overlap, therefore the existence of these phases cannot, fo r certain, be claimed from this data. However, the N/C atomic ratio is clos e to the stoichiometric value 1.33. X-Ray photoelectron spectroscopy (XPS) analysis indicated that the binding energies of C 1s and N 1s are 286.43 an d 399.08 eV, respectively. The shifts are attributed to the polarization of the C-N bond. Both observed Raman and Fourier transform infrared (FT-IR) s pectra were compared with the theoretical calculations. The results support the existence of a C-N covalent bond in the films. (C) 2000 Published by E lsevier Science S.A. All rights reserved.