Analysis and numerical modelling of silicon nitride deposition in a plasma-enhanced chemical vapour deposition reactor. I. Bidimensional modelling

Abstract

A numerical model of silicon nitride deposition from an NH,-SiH, mixture in a largesized radiofrequency plasma reactor has been developed. A bidimensional treatment of transpolt phenomena, of major importance in this type of reactor, was used. Analysis of the modelling results showed that aminosilane radicals were the main deposition precursors. The steep decrease in deposition rate in the flow direction that was observed can be explained by examining the calculated concentration profiles. Concentration of ith species (mol m-3) Initial concentration of ith species (mol m -3, Diffusion coefficient of ith species in the mixture (m's-l) Electron impact dissociation constant (m3s-') Electron impact ionization constant (m3s-l) Rate constant of reaction i (mol-' m3 s-l) Molar mass on species i (kgmol-') Electronic density Pressure (Pa) Volumic flow rate of species A Ideal gas constant (8.32Jmol-' K-') Deposition rate (ms-I) Reaction term in the gas phase (m01m~s-l) Reaction term at a surface (molm2s-') Sticking coefficient of the ith species Deposition temperature (K) Axial velocity (ms-') Radial velocity (ms-') Electrical power dissipated in the discharge (W) C0!!ip,ip'on \re!p'ocity

Study of the composition of hydrogenated silicon nitride SiNx:H for efficient surface and bulk passivation of silicon

“…This could be attributed to the low frequency plasma process, as it has been already observed [31,32]: the composition of the SiN films remains far from the stoichiometry (x = 1.33). The dissociation and activation of the reactive species issued from ammonia needs much more energy than for the silane radicals [33,34]. For the deposition temperatures considered, and since low frequency is used for plasma excitation, the NH 3 reactive species density is believed to stay low in spite of the increasing of the NH 3 gas flow.…”

Influence of the nitrogen flow rate on the order and structure of PECVD boron nitride thin films

“…There are several nonuniformity sources along the electrode radius of a capacitively coupled PECVD reactor such as perturbation of electric field lines at the electrode edges [41], standing wave effect [42], plasma potential nonuniformity [43], gas injection distribution [44], etc. In the literature, the growth rate of pure boron is reported to be higher than that of BN [45].…”

Parameter Study by Infrared and Morphological Investigations of Plasma-Polymerised Thin Silicon Nitride Films Deposited with the Plasmodul

“…Two bands are absorptions with hydrogen groups. The [NH] band vibration at 1 180 cm −1 and the band vibration of the [SiH] group at 645 cm −1 complete the whole SiN band 3–6. The three different coatings displayed in Figure 3 show that the different vibration bands change their absorption intensity by varying the amount of SiH 4 (20, 42, 50%) in the total flux.…”

“…silicon wafer or plastic foils, a remote setup was chosen, where the SiH 4 is fed into the afterglow between the plasma and the substrate. The reaction follows the equation3 …”