Characterization of a-C:H:N deposition from CH4/N2 rf plasmas using optical emission spectroscopy

Abstract

Optical emission spectra ͑OES͒ from CH 4 /N 2 rf plasmas, which are used for the deposition of nitrogen-containing hydrogenated amorphous carbon ͑a-C:H:N͒ thin films, have been characterized. Previously unidentified spectral lines have been assigned to atomic N. Further identified species include CH, H, H 2 , N 2 , N 2 ϩ , N, and CN. Variations between spectra from the pure CH 4 or N 2 plasmas and the mixed CH 4 /N 2 plasma are discussed. The enhancement of excited nitrogen species, with the addition CH 4 , is attributed to Penning ionization. The observed OES variations of the CH 4 /N 2 plasma with power, pressure, and CH 4 /N 2 ratio are explained in terms of possible reaction mechanisms and their activation, and correlated with preliminary film growth characteristics.

IR characterization of a-C:H:N films sputtered in Ar/CH4/N2 plasma

“…Various kinds of preparation methods have been applied to fabricate carbon nitride films, but samples with sufficient amount of crystallized C 3 N 4 phase or with mechanical properties comparable to the predicted values have not been reported. The internal stress considerably decreases with the addition of nitrogen, without sacrificing hardness, up to an N incorporation of 2%, by the decrease of the amount of unbound hydrogen in the film [4,5]. At higher concentrations, hardness is reduced due to the development of graphitic domain.…”

Spectroscopic visualization of CH in methane/hydrogen plasmas for synthesis of carbonaceous materials and surface micromorphology

“…It has been known that PECVD is a promising process to obtain inorganic films [1], and most widely used to synthesize carbonaceous materials for their unique chemical, electrical and mechanical properties [2]. However, the resulting film properties varied significantly depending on the PECVD conditions.…”

Time Resolved Spectroscopic Characterization of a-C:H Deposition by Methane and Removal by Oxygen Inductively Coupled RF Plasma

“…Therefore, the fit to corresponding expressions for the time dependence of reflection coefficients could be used for extracting thickness [25]. We note that deposition rates could be influenced significantly by the presence of various impurities such as nitrogen where the level of impurities could not be seen from the total gas pressure, but only from the OES observation [26]. All results presented here are for the case when no impurities, such as CN (B-X) molecular band at 388 nm, could be observed in spectra.…”