Electron cyclotron resonance plasma deposition as a promising technique for low-temperature hard coatings

Abstract

Si 3N 4 and SiC films have been deposited by electron cyclotron resonance (ECR) plasma at low substrate temperature (T s ⩽150°C). Films prepared by this new technique exhibited better properties than those deposited by other plasma methods. Different gas ratios and microwave powers have been used. The films have been analysed by infrared spectrometry and spectroscopic ellipsometry. Si 3N 4 and SiC films show in general a good thickness homogeneity (< 4% in 3 in. wafers) and reproducibility. Depending on the process parameters we have found growth rates up to 3500 Åmin −1 for Si 3N 4 and 400 Åmin −1 for SiC. The infrared spectra of these layers have shown no signal of SiH and NH bonds in the Si 3N 4 films and low traces of SiH and CH n bonds in the SiC films.