Influence of the power on the processes controlling the formation of ECR-CVD carbon nitride films from CH4/Ar/N2 plasmas

Abstract

Carbon nitride films have been synthesized by means of electron cyclotron resonance chemical vapour deposition (ECR-CVD) using different power values (50–212 W) at constant pressure conditions (0.03 mbar). Optical emission spectroscopy and mass spectrometry were used for the characterization of the plasma. The films were analysed using energy dispersive x-ray spectroscopies. It was found that all signal peaks in the optical emission spectra increased monotonically following the increase in microwave power. Moreover, we have observed that the radiative emission from the 4p(2p9) resonant state of Ar is the most affected by CH4 addition to a pure argon plasma. The latter suggests that a Penning mechanism controls the activation of CH4 molecules with increasing power levels at relatively low pressures. Besides, the increase of excited N atoms indicates a higher activity of the etching mechanisms of carbon nitride films with increasing power.