On-line gas-phase optical diagnostics in plasma CVD deposition of carbon films

Abstract

Space resolved, on-line spontaneous and stimulated emission, and CARS diagnostics have been employed on CH 4 /H 2 mixtures excited by rf-discharge in order to investigate the chemical processes and the gas phase kinetics in the plasma. CH 4 and H 2 concentration and temperature have been monitored during the process as a function of main reaction parameters (rf-power, total pressure, CH 4 /H 2 ratio). Formation of CH,H2, and H in excited states has been observed. On the basis of present spectroscopic data, a model for the gas-phase reactions accompanying the carbon film deposition is proposed.

SOFC anodes for direct oxidation of hydrogen and methane fuels containing H2S

“…However these added techniques are not necessarily required and the high temperatures of the fuel cell may produce the same results. There is a large body of literature in which carbon films are formed by CVD using methane and hydrogen as precursor gases [43][44][45]. Typically temperature and precursor ratios control the film structure from amorphous to crystalline.…”