Characterization of a N₂/CH₄ Microwave Plasma With a Solid Additive Si Source Used for SiCN Deposition

Abstract

Microwave plasma assisted chemical vapour deposition of CH4/N2 gas mixture using an additive solid silicon is used to synthesize SiCN. To better understand the mechanisms involved, species such as C, Si, NH, CN, C2 and N2 are observed by means of optical emission spectroscopy. In situ Fourier transform infrared spectroscopy (FTIR) is used as a plasma diagnostic and CH4, NH3, HCN and C2H2 have been detected. Deposits are achieved at various CH4 ratios (1, 4 and 8%) and analysed by means of scanning electron microscopy, energy dispersion X‐ray spectroscopy and FTIR spectroscopy. Adding a silicon source permits to obtain thicker layers confirming the major role of Si in the carbonitride deposition process. Deposits obtained at 8% of CH4 have a composition about 35% of Si, 30% C and 30% N and showed evidence of ternary SiCN system.

Influence of Deposition Conditions on the Characteristics of Luminescent Silicon Carbonitride Thin Films

“…These two emission lines were found to be the major components in the gas mixture, which lead to the relatively low concentration of C-N bonds in CVD grown thin films. 41 Higher reactivity of CH 4 at higher substrate temperature yields less formation of hydrogen cyanide, HCN, providing the opportunity for the formation of C-N bonds in the film.…”

Microwave Plasma Process for SiCN:H Thin Films Synthesis with Composition Varying from SiC:H to SiN:H in H2/N2/Ar/Hexamethyldisilazane Gas Mixture

“…[25][26][27] The gas purity is 99.99%. During the film growth, the substrate temperature is maintained at 4008C which is a temperature compatible with photovoltaic industrial processes.…”

“…SiC x N y :H thin films are grown on Si(100) and fused silica substrates in a homemade microwave resonant plasma cavity (2.45 GHz) . The gas purity is 99.99%.…”

CVD synthesis of multi-layered polycrystalline diamond films with reduced roughness using time-limited injections of N2 gas

“…This time can be viewed as the "relaxation" time for the gas concentration to reach new equilibrium state of newly set proportion of the gases in the chamber. The optical emission spectroscopy (OES, OceanOptics 4000 instrument) was used for the precise determination of such relaxation time by the dynamic of change of integrated intensity of CN band (violet band system, Δv = -1) near 421 nm [50,51]. This particular band was chosen due to absence of interfering peaks of standard H2-CH4 plasma (see Fig 2a).…”