FORMATION OF CARBON NITRIDE FILMS BY HELICON WAVE PLASMA-ENHANCED DC SPUTTERING

Carbon nitride films have been synthesized on Si(100) substrates by us ing DC sputtering assisted with a high density m = 0 mode helicon wave -excited plasma in Ar and N-2 mixture. The composition, structure and bonding state of the films were investigated by X-ray photoelectron sp ectroscopy (XPS) and Fourier transform infrared (FT-IR) spectroscopy. From the XPS analysis it was found that the nitrogen to carbon (NIC) r atio in the films could be controlled over a wide range of 0.2-0.9 by changing the target voltage and nitrogen mixing rate via the productio n of a high density plasma of 10(12)-10(13) cm(-3). FT-IR spectroscopy indicated the appearance of an absorption band near 2200 cm(-1) corre sponding to C=N covalent bonding. The XPS analysis also suggested the existence of a beta-C3N4 phase-with sp(3) bonding correlated with the variation of the film microhardness.